"Influence of Cognitive Style in a Methodology for Data Base Des ign" Ronald R. Bush. Research Report

Transcription

1 TECHNICAL REPORT STANDARD TITLE PAGE 1. Reprt N. 2. Gyermet Accessi N. 3. Recipiet'. Catalg N. 4. Title ad ~ubtitle "Ifluece f Cgitive Style i a Methdlgy fr Data Base Des ig" 7. Authr'.) Rald R. Bush 5. Reprt Date February Perfrmig Orgi zati Cde 8. Perfrmig Orgaizati Reprt N. Research Reprt Perfrmig Orgaizati Name ad Address Ceter fr Highway Research The Uiversity f Texas at Austi Austi, Texas ~.~~ ~~ ~ 12. Sp.rig Agecy Name ad Addre.. Texas Highway Departmet Plaig & Research Divisi P.O. Bx 5051 Austi, Texas Supplemetary Nte. 10. Wrk Uit N. 11. Ctract r Grat N. Research Study Type f Reprt ad Perid Cyered 14. Spsrig Agecy Cde Wrk de i cperati with the Federal Highway Admiistrati, Departmet f Trasprtati. Research Study Title: "A SystemAalysis f Pavemet Desig ad Research Implemetati" 16. Ab.tract The rapid prliferati f cmputerized ifrmati systems has created a urget eed fr better methds t determie what the ctets f the data bases fr these systems shuld be. The cetral theme uderlyig the methdlgy, which is prpsed fr makig this determiati, is that there are certai types f ifrmati ccerig what the ctets f a data base shuld be that ca be best prvided by the mst kwledgeable peple i the area, i.e. the ptetial users f the system. A ccurret csiderati, which als makes it highly desirable t have the ptetial users ivlved i the develpmet f their system, is that participati i decisi makig has bee shw t lead t greater grup acceptace. This aspect f ptetial user ivlvemet is especially imprtat, sice grup acceptace is critical t the success f ay ifrmati system. A Delphi type methdlgy prvides a meas whereby the piis f the ptetial users ca be effectively itegrated i regard t the types f data that are imprtat i a data base. Prcedures fr implemetig the methdlgy are develped, ad a geeralized cmputer prgram fr prcessig the ifrmati flws assciated with the methd is described. The descripti f a actual applicati f the methd t the desig f the data base fr the Pavemet Feedback Data System (PFDS), which is curretly uder develpmet i the Texas Highway Departmet, is used as a example t illustrate the ccepts ivlved. 17. Key Wrd. 18. Distributi Statemet Delphi prcess, Pavemet Feedback Data System (PFDS), cgitive style 19. Securi ty Claif. (f thi. reprt) 20. Security Clalf. (f thi. pge) Uclassified Uclassified 21. N. f Page. 22. Pri ce 250 Frm DOT F (SU)

2 INFLUENCE OF COGNITIVE STYLE IN A METHODOLOGY FOR DATA BASE DESIGN by Rald R. Bush Research Reprt Number A System Aalysis f Pavemet Desig ad Research Implemetati Research Prject cducted i cperati with the U. S. Departmet f Trasprtati Federal Highway Admiistrati by the Highway Desig Divisi Texas Highway Departmet Texas Trasprtati Istitute Texas A&M Uiversity Ceter fr Highway Research The Uiversity f Texas at Austi February 1975

3 The ctets f this reprt reflect the views f the authr, wh is respsible fr the facts ad the accuracy f the data preseted herei. The ctets d t ecessarily reflect the fficial views r plicies f the Federal Highway Admiistrati. This reprt des t cstitute a stadard, specificati, r regulati. ii

4 PREFACE This reprt results frm research cducted uder Research Prject N , I~ System Aalysis f Pavemet Desig ad Research Implemetati." The prject was iitiated i 1969 ad is beig cducted jitly by the Texas Highway Departmet, the Ceter fr Highway Research, ad the Texas Trasprtati Istitute. The study is part f a cperative research prgram with the Departmet f Trasprtati Federal Highway Admiistrati. This study was cducted t btai the backgrud ecessary t establish a autmated data feedback system, called the Pavemet Feedback Data System (PFDS). This system wuld be f great beefit i the areas f pavemet research, desig, ad maiteace. The study discussed herei prduced a tetative list f items fr the PFDS, a ratig assiged by the Delphi participats f the imprtace f each item, ad a list f reprted redudacies i the set f items. It is felt that this ifrmati, which has bee made available t the Texas Highway Departmet, will serve as a basis fr the frmulati f a defiite set f items fr iclusi i PFDS. The authr. gratefully ackwledges the assistace ad ecuragemet f Dr. Timthy Ruef1i. The authr als ackwledges the ctributis f Drs. Kight, Hward, Huds, ad MCCullugh. Mr. Hugh Williams f the Ceter fr Highway Research prpsed the statistical prcedure used t test fr differeces betwee data base desigs. Withut his assistace i this area the quality f the study wuld have suffered sigificatly. Mr. James L. Brw f the Texas Highway Departmet made may valuable suggestis regardig the Delphi prcedures. Nt ly did his recmmedatis ctribute t the effectiveess f the Delphi prcess i the Highway Departmet, but may f the prcedures he suggested will udubtedly be icrprated i subsequet applicatis f the methd. The 241 idividuals frm the Texas Highway Departmet, Ceter fr Highway Research, ad Texas Trasprtati Istitute, wh participated i the PFDS iii

5 iv data base desig prject, each deserve a special wrd f thaks. Their diligece ad dedicati made the prject a success; ad I am prud t have bee assciated with such a utstadig grup. Rald R. Bu.sh February 1975

6 LIST OF REPORTS Reprt N , "A Systems Apprach Applied t Pavemet Desig ad Research," by W. Rald Huds, B. Frak McCullugh, F. H. Scriver, ad James L. Brw, describes a lg-rage cmprehesive research prgram t develp a pavemet systems aalysis ad presets a wrkig systems mdel fr the desig f flexible pavemets. March 1970 Reprt N , '~ Recmmeded Texas Highway Departmet Pavemet Desig System Users Maual," by James L. Brw, Larry J. Buttler, ad Hug E. Orellaa, is a maual f istructis t Texas Highway Departmet persel fr btaiig ad prcessig data fr flexible pavemet desig system. March 1970 Reprt N , "Characterizati f the Swellig Clay Parameter Used i the Pavemet Desig System," by Arthur W. Witt, III, ad B. Frak McCullugh, describes the results f a study f the swellig clays parameter used i pavemet desig system. August 1970 Reprt N , ''Develpig A Pavemet Feedback Data System," by R. C. G. Haas, describes the iitial plaig ad develpmet f a pavemet feedback data system. February 1971 Reprt N , "A Systems Aalysis f Rigid Pavemet Desig," by Ramesh K. Kher, W. R. Huds, ad B. F. McCullugh, describes the develpmet f a wrkig systems mdel fr the desig f rigid pavemets. Nvember 1970 Reprt N , "Calculati f the Elastic Mduli f a Tw Layer Pavemet System frm Measured Surface Deflectis," by F. H. Scriver, C. H. Michalak, ad William M. Mre, describes a cmputer prgram which will serve as a subsystem f a future Flexible Pavemet System fuded liear elastic thery. March 1971 Reprt N A, "Calculati f the Elastic Mduli f a Tw Layer Pavemet System frm Measured Surface Deflectis, Part II," by Frak H. Scriver, Chester H. Michalak, ad William M. Mre, is a supplemet t Reprt N ad describes the effect f a chage i the specified lcati f e f the deflecti pits. December 1971 Reprt N , "Aual Reprt Imprtat Pavemet Research Needs," by B. Frak McCullugh, James L. Brw, W. Rald Huds, ad F. H. Scriver, describes a list f pririty research items based fidigs frm use f the pavemet desig system. April 1971 Reprt N , "A Sesitivity Aalysis f Flexible Pavemet System FPS2," by Ramesh K. Kher, B. Frak McCullugh, ad W. Rald Huds, describes the verall imprtace f this system, the relative imprtace f the variables f the system ad recmmedatis fr efficiet use f the cmputer prgram. August 1971 v

7 vi Reprt N , "Skid Resistace Csideratis i the Flexible Pavemet Desig System," by David C. SteHle ad B. Frak McCullugh, describes skid res istace csiderati i the Flexible Pavemet System based the testig f aggregates i the labratry t predict field perfrmace ad presets a mgraph fr the field egieer t use t elimiate aggregat,as which wuld t prvide adequate skid resistace perfrmace. April 1972 Reprt N , '~lexib1e Pavemet System - Secd Geerati, Icrpratig Fatigue ad Stchastic Ccepts," by Suredra Prakash Jai, B. Frak McCullugh ad W. Rald Huds, describes the develpmet f ew struct:.lra1 desig mdels fr the desig f flexible pavemet which will replace the empirical relatiship used at preset i flexible pavemet systems t simulate the trasfrmati betwee the iput variables ad perfrmace f a pavemet. Jauary 1972 Reprt N , '~lexib1e Pavemet System Cmputer Prgram Dcumetati," by Dale L. Schafer, prvides dcumetati ad a easily updated dcumetati system fr the cmputer prgram FPS-9. April 1972 Reprt N , "A Pavemet Feedback Data System," by Ore G. Strm, W. Rald Huds, ad James L. Brw, defies a data system t a~quire, stre, ad aalyze perfrmace feedback data frm i-service f1exib1,a pavemets. May 1972 Reprt N , ''Beefit Aalysis fr Pavemet Desig Syst,am," by Frak McFarlad, presets a methd fr relatig mtrist's csts t the pavemet serviceability idex ad a discussi f several differet methds f ecmic aalysis. April 1972 Reprt N , "Predicti f Lw-Temperature ad Thermal-Fatigue Crackig i Flexible Pavemets," by Mhamed Y. Shahi ad B. Frak McCullugh, describes a desig system fr predictig temperature crackig i asphalt ccrete surfaces. August 1972 Reprt N , '~PS-11 Flexible Pavemet System Cmputer Prgram Dcumetati," by Hug E. Orellaa, gives the dcumetati f the c:puter prgram FPS-ll, Octber 1972~ April 1972 Reprt N , '~atigue ad Stress Aalysis Ccepts fr :~difyig the Rigid Pavemet Desig System," by Piti Yimprasett ad B. Frak McCullugh, describes the fatigue f ccrete ad stress aalyses f rigid pavemet. Octber 1972 Reprt N , "The Optimizati f a Flexible Pavemet System Usig Liear Elasticity," by Day Y. Lu, Chia Shu Shih, ad Frak H. Scriver, describes the itegrati f the curret Flexible Pavemet System cmputer prgram ad Shell Oil Cmpay's prgram BISTRO, fr elastic layered systems, with special emphasis ecmy f cmputati ad evaluati f structural feasibility f materials. March 1973 Reprt N , "Prbabilistic Desig Ccepts Applied t Flexible Pavemet System Desig," by Michael 1. Darter ad W. Rald Huds, describes the develpmet ad implemetati f the prbabilistic desig apprach ad its icrprati it the Texas flexible pavemet desig system fr ew cstructi ad asphalt ccrete verlay. May 1973

8 vii Reprt N , "The Use f Cditi Surveys, Prfile Studies, ad Maiteace Studies i Relatig Pavemet Distress t Pavemet Perfrmace," by Rbert p. Smith ad B. Frak McCullugh, itrduces the area f relatig pavemet distress t pavemet perfrmace, presets wrk accmplished i this area ad gives recmmedatis fr future research, August Reprt N , "Implemetati f a Cmplex Research Develpmet f Flexible Pavemet Desig System it Texas Highway Departmet Desig Operatis," by Larry Buttler ad Hug Orellaa, describes the step by step prcess used i icrpratig the implemetati research it the actual wrkig perati. Reprt N , "Rigid Pavemet Desig System, Iput Guide fr Prgram RPS2 i Use by the Texas Highway Departmet," by Rbert F. Carmichael ad B. Frak McCullugh, describes the iput f variables ecessary t use i the Texas rigid pavemet desig system prgram RPS2, May Reprt N , "A Itegrated Pavemet Desig Prcessr," by Day Y. Lu, Chia Shu Shih, Frak H. Scriver ad Rbert L. Lytt, prvides a cmprehesive decisi framewrk with a capacity t drive differet pavemet desig' prgrams at the user's cmmad thrugh iteractive queries betwee the cmputer ad the desig egieer. Reprt N , "Stchastic Desig Parameters ad Lack-f-Fit f Perfrmace Mdel i the Texas Flexible Pavemet Desig System," by Malvi Hlse ad W. Rald Huds, describes a study f iitial serviceability idex f flexible pavemets ad a methd fr quatifyig 1ack-f-fit f the perfrmace equati. Reprt N , "The Effect f Varyig the Mdulus ad Thickess f Asphaltic Ccrete Surfacig Materials," by Day Y. Lu ad Frak H. Scriver, ivestigates the effect the pricipal stresses ad strais i asphaltic ccrete resultig frm varyig the thickess ad mdulus f that material whe used as the surfacig f a typical flexible pavemet (beig prepared fr submissi). Reprt N , '~lastic Layer Thery as a Mdel f Displacemets Measured Withi Flexible Pavemet Structures Laded by the Dyaf1ect," by Frak H. Scriver et a1, describes the fittig f a empirical mdel t the study f 136 (TTl) data (beig prepared fr submissi). Reprt N , 'Mdificati ad Implemetati f the Rigid Pavemet Desig System," by Rbert F. Carmichael ad B. Frak McCullugh, describes the ew RPS-3 versi f the rigid pavemet desig system i detail ad cmplete with a iput guide, dcumetati, ad listig.

9 viii Reprt N , "Ifluece f Cgitive Style i a Methdlgy fr Data Base Desig," by Rald R. Bush, icludes a treatmet f the Delphi prcess applied t the desig f the Pavemet Feedback Data System.

10 ABSTRACT The rapid prliferati f cmputerized ifrmati systems has created a urget eed fr better methds t determie what the ctets f the data bases fr these systems shuld be. The cetral theme uderlyig the methdlgy, which is prpsed fr makig this determiati, is that there are certai types f ifrmati ccerig what the ctets f a data base shuld be that ca be best prvided by the mst. kwledgeable peple i the area, i.e. the ptetial users f the system. A ccurret csiderati, which als makes it highly desirable t have the ptetial users ivlved i the develpmet f their system, is that participati i decisi makig has bee shw t lead t greater grup acceptace. This aspect f ptetial user ivlvemet is especially imprtat, sice grup acceptace is critical t the success f ay ifrmati system. A Delphi type methdlgy prvides a meas whereby the piis f the ptetial users ca be effectively itegrated i regard t the types f data that are imprtat i a data base. Prcedures fr implemetig the methdlgy are develped, ad a geeralized cmputer prgram fr prcessig the ifrmati flws assciated with the methd is described. The descripti f a actual applicati f the methd t the desig f the data base fr the Pavemet Feedback Data System (PFDS), which is curretly uder develpmet i the Texas Highway Departmet, is used as a example t illustrate the ccepts ivlved. The Delphi prcess als prvides a effective research methdlgy fr ivestigatig the effects that certai persal characteristics f the ptetial users have the data base desigs achieved. The cgitive styles f the Delphi participats i the PFDS study were assessed alg the fielddepedet/idepedet dimesi as measured by the Hidde Figures Test. The the ifluece f cgitive style the data base desigs achieved by differet Delphi grups was ivestigated. It was ccluded that Delphi grups, cmpsed f participats with differet cgitive styles, cverge t data base desigs that are sigificatly differet frm e ather. ix

11 x The effect f Delphi participati the attitudes f the ptetial users tward the system was als ivestigated i the PFDS study. A small but statistically sigificat, verall psitive chage i attitude was bserved after the ptetial users had participated i the data base desig prcess. The successful applicati f a Delphi type methdlgy t the desig f the PFDS data base has prve that the prcess prvides a viable methd fr ivlvig the ptetial users i the desig f their system. Furthermre, it is ccluded that the methd pssesses excellet ptetial fr widespread applicati i the area f data base desig. KEY WORDS: style. Delphi prcess, Pavemet Feedback Data System (PFDS), cgitive

12 SUMMARY It has becme evidet i dealig with the decisis faced by pavemet egieers that a vast amut f past experiece exists which, if available? wuld be f great beefit. Perhaps the mst practical methd f makig such ifrmati readily available is thrugh the meas f a cmputerized data base. By capturig ad strig data frm i-service pavemets as well as ew cstructi, a ivetry f the Texas pavemet etwrk ca be established i the frm f a cmputerized data base residet the Texas Highway Departmet (THO) System 370 i Austi. This Pavemet Feedback Data System (PFDS) ca the be used fr research, desig, ad maagemet fuctis. It is iteded that this ifrmati will supplemet the pavemet egieer's judgmet ad assist him i makig better pavemet decisis. I determiig what ifrmati shuld be stred i PFDS, care must be exercised s that all ecessary ifrmati will be available whe eeded, while ther items shuld be excluded frm the system as their presece wuld ly icrease the peratig csts. The ptetial users f the system, wh als ted t be the mst kwledgeable peple i the area f pavemet-related prblems, are best suited fr prvidig the ctets f the PFDS data base. Hwever, it is difficult fr a large grup f peple t agree smethig as ivlved as the set f items t be stred a cmputerized ifrmati system. Thus, the Delphi prcess is used whereby each idividual makes his ctributis free frm the psychlgical frces f the grup. By a prcess f iteratis, i which each pers recsiders his judgmet i light f the grup csesus frm the previus iterati, the idividuals f the grup begi t cverge i their ideas. Thus, the items t be ctaied i the data base are btaied. The Delphi prcess was used i this study t geerate a prpsed list f items fr iclusi i a Texas Pavemet Feedback Data System. The list, tgether with accmpayig ifrmati icludig imprtace ratigs assiged t all the items by the Delphi participats, is preseted i this reprt. The xi

13 xii list is pssibly the mst imprtat practical result f this3tudy, sice it relates directly t the implemetati f PFDS. A discussi is als give the relatiship betwee the cgitive style f the participats ad their prefereces abut the cmpsiti f the data base. The participats were raked a glbal-aalytical cgitive style ctiuum by meas f certai testig prcedures applied befre the Delphi experimet. The fllwig specific results were btalled: (1) The umber f data items iitially submitted by the participats is crrelated with their cgitive styles. (2) Hmgeeus Delphi grups, cmpsed f participats with differet cgitive styles, cverged t data base desigs that were sigificatly differet frm each ther. (3) The maer i which the Delphi grups are structured, relative t cgitive style, appears t be a imprtat cside:rati t ly i regard t the data base desig achieved, but als i regard t the degree t which the subjects are able t participate effectively i the prcess. The glbal type f idividual appears t fucti better i a grup cmpsed slely f ther glbal types. Fially, a imprvemet i the attitude f the participalts tward the data base was achieved by their takig part i the Delphi pr:ess. The imprvemet was small, but statistically sigificat at the.05 level.

14 IMPLEMENTATION STATEMENT This study has yielded a tetative set f items fr iclusi i PFDS, a list f items i the set which appear t be redudat, ad a imprtace ratig assiged t each item. This ifrmati prvides the basis fr the frmulati f a defiite set f data items fr iclusi i the prelimiary PFDS. The list ad imprtace ratigs are especially useful sice they were btaied frm ptetial users f the data base withi the Texas Highway Departmet ad supprtig research istitutis ad thus reflect the iterest ad kwledge f field persel. Recmmedatis fr use f the prpsed set f data items i desigig PFDS are give belw fllwig a brief summary f ecessary backgrud ifrmati which is discussed i detail i the reprt. Fr the purpses f studyig the effect f certai persality factrs the prefereces abut PFDS data items, the participats were classified it five categries the basis f iitial testig. Differeces betwee peple wh ted t thik i aalytical ad thse wh thik i brad r glbal terms were ivestigated. Additially, thse with a iitial lw attitude abut the data base were studied separately. The participats were divided it 21 separate grups, icludig fur replicate grups withi each f fur persality classificatis, fur ctrl grups, ad a late etry grup. Each f the 21 grups selected its w prpsed list f items fr PFDS by the Delphi prcess, which is discussed i the bdy f this reprt. Thus, the iitial utcme f the experimet was 21 separate prpsed lists f items. All f the items icluded by ay f the grups are listed i Appedix F alg with the average imprtace ratig assiged t each item by the grups which icluded the item. fr each item is as fllws: The additial ifrmati prvided i the appedix (1) the umber f grups ut f 21 which icluded the item, (2) the lwest ad highest f the imprtace ratigs assiged t the item by the grups that icluded it, ad xiii

15 xiv (3) additial ifrmati idicatig which specific grups icluded the item. Tw steps are w eeded t prduce a defiite set f items fr iclusi i the prelimiary PFDS: elimiati f redudacies i the list ad selecti f the items frm the resultig duplicati-free list fr actual iclusi. The elimiati f redudacies will be greatly facilitated by the list f duplicatis reprted durig the experimet by the participats. This list is als give i Appedix F. Further examiati will be required, hwever, t elimiate all redudacies ad chse the best f each set f alterate terms. The selecti f the items frm the duplicati-free list fr actual iclusi will be aided csiderably by the imprtace ratigs assiged all prpsed items by the participats i the study. the fllwig verbal meaigs: 5.0 Imperative that item be icluded 4.0 Highly imprtat 3.0 Mderately imprtat 2.0 Of questiable imprtace 1.0 Lw imprtace 0.0 Abslutely imprtace. The imprtace ratigs have Clearly, ay scheme fr selectig part f the list f prpsed items will ivlve sme subjectivity, but the imprtace ratigs prvide a basis fr a systematic apprach. The fllwig are recmmedatis fr Euch a apprach. First, it is suggested that items with average imprtace ratigs f 3.0 r higher be icluded, whereas all items with a value f 2.0 r lwer be excluded frm the fial list. Ay item give at least e,tig f 4.0 r higher shuld prbably be icluded, sice at least e f the: 21 grups csiders that item t be highly imprtat. Fr margial items, it is suggested that bth the umber f grups that icluded the item ad the rage f imprtace ratigs be csidered. A large rage idicates a substatial diversity i feelig tward a item; if there are a few high ratigs, iclusi may be warrated, eve thugh the average is lw.

16 TABLE OF CONTENTS PREFACE LIST OF REPORTS ABSTRACT iii v ix SUMMARY xi IMPLEMENTATION STATEMENT xiii CHAPTER 1. INTRODUCTION The Need fr Data Base Desig Techiques 1 The Delphi Techique 2 Cgitive Style 5 Pavemet Feedback Data System (PFDS) 7 Ratiale ad Limitatis 13 Summary f Research Objectives 14 Scpe f the Reprt 15 CHAPTER 2. REVIEW OF THE LITERATURE Delphi 17 Cgitive Style 28 Summary 38 CHAPTER 3. A DELPHI METHODOLOGY FOR DATA BASE DES IGN Types f Ifrmati 41 Delphi Prcedures 47 Delphi Cmputer Prgram 52 PFDS Prject 54 Summary 58 CHAPTER 4. RESEARCH DES IGN Hyptheses 59 Experimetal Desig 60 Surmary 69 xv

17 xvi CHAPTER 5. MEASUREMENT INSTRUMENTS Hidde Figures Test Attitude Scale.. Summary CHAPTER 6. COGNITIVE STYLE AND THE ARTICULATION OF DATA ITEMS Nature f the Task Crrelati Fud i PFDS Experimet Summary CHAPTER 7. COMPARISON OF DELPHI DESIGNS Expected Differeces Statistical Methd PFDS Experimet Results Cgitive Style Cmpariss Attitude Cmpariss Ubtrusive Measures Summary CHAPTER 8. DELPHI: A SUBJECTIVE APPRAISAL Delphi i Perspective Delphi i PFDS Cst vs. Beefit Admiistratr Observatis Summary CHAPTER 9. EFFECT OF USER PARTICIPATION IN THE DESIGN PROCES':; Expectatis Regardig particip~i Statistical Methd ad PFDS Resu ts Discussi f the Results Summary CHAPTER 10. CONCLUSIONS AND RECOMMENDATIONS Cclusis Rec uedat is Accmplishmets Implicatis

18 xvii APPENDICES Appedix A. Appedix B. Appedix C. Appedix D. Appedix E. Appedix F. Istructis fr PFDS Data Base Desig Prject Delphi Prgram PFDS Grup Prituts Cgitive Style ad Attitude Scales Participat Data Tetative List f Items fr PFDS... REFERENCES

19 CHAPTER 1. INTRODUCTION The last few years have witessed the rapid begiig f what is predicted t be a majr mvemet tward the istallati f cmputerized data base systems i rgaizatis. This mvemet has bee ad is beig fueled by ur ctiuig prgress i cmputer techlgy. If the expected prgress i the areas f lw-cst, high-capacity, radm access devices ad strage maagemet techiques materializes, the grwth i the istallati rate f data base systems may well be explsive. Ufrtuately, this rapid techlgical prgress i ur ability t istall data base systems has bee utstrippig ur uderstadig f what the data ctets f these systems shuld be. Therefre, the research effrt described i this reprt was udertake with the bjective f develpig ad refiig a data base desig methdlgy that will help t clse the heretfre grwig gap betwee ur techlgical capability ad ur ability t desig data base systems that ctai data which will effectively aid maagemet decisi makig. The Need fr Data Base Desig Techiques Jerme Kater (Ref 51, p 213) discusses the results f a study, t evaluate the relative imprtace f ptetial MIS research prjects, that was cducted by the Sciety fr Maagemet Ifrmati Systems durig its fudig cferece i The cferece was atteded by 125 idividuals wh represeted a wide crss secti f highly experieced MIS prfessials. These idividuals were asked t rak twety-six ptetial MIS research prjects i relati t their perceived imprtace, ad a cmpsite rakig f the grup's pii was the develped. i the rder f their relative imprtace were: The three mst highly raked prjects (1) develpmet f methds fr determiig what the ctet f a ifrmati system shuld be, (2) ivestigati it the characteristics f decisi makers which affects MIS system desig, ad 1

20 2 (3) ivestigati f meas fr vercmig user-desiger i'terface prblems. (Ref 51, p 216) Sice it is difficult t imagie hw aye f the three tp raked prjects culd be successfully cmpleted withut givig at least partial atteti t the ther tw, this authr views the csiderati's embedded i the prjects as beig iseparable. Therefre, it was deemed essetial that bth the data base desig methdlgy ad the experimetal desig, described i this reprt, address all three f the abve csideratis. Further ad mre recet evidece f the pressig eed fr better data base desig techiques ca be fud i "A Study f Critical Factrs i Maagemet Ifrmati Systems fr U.S. Air Frce" (Ref 12) that '~as i 1973 at Clrad State Uiversity. cducted I this study, persel frm a widely diversified sample f busiess rgaizatis ad gvermet agecies were iterviewed with the bjective f determiig what factrs are mst critical i ifrmati systems desig. I the list f twety critical factrs that was develped, "idetificati f ifrmati eeds f maagemet" was raked secd, just barely behid the first raked factr which was "defiiti f bjectives f the system" (Ref 12, p 9). Ibere is little dubt that e f the fremst prblems facig the ifrmati systems desiger tday is hw t determie what the ctet f a ifrmati system shuld be. This reprt examies a Delphi methdlgy fr data base desig that appears t ffer great ptetial fr vercmig this prblem. The Delphi Techique The "Delphi Techique," a gig prject f the Rad Crprati which was begu shrtly after Wrld War II, is a methd fr achievig a reased csesus f pii amg a grup f experts. The purpse f the methd is t avid the direct cfrtati f the experts by meas f a iterative iterrgati scheme i which ly the admiistratr is aware f the surces f ifrmati which is fed back t the participats. A ccise but detailed descripti f the techique is give by Helmer wh was e f the may ctributrs t the methd. The "Delphi Techique," elimiates cmmittee activity, thus further reducig the ifluece f certai psychlgical factrs, such as

21 3 specius persuasi, the uwilligess t abad publicly expressed piis, ad the badwag effect f majrity pii. This techique replaces direct debate by a carefully desiged prgram f sequetial idividual iterrgatis (best cducted by questiaires) iterspersed with ifrmati ad pii feedback derived by cmputed csesus frm the earlier parts f the prgram. Sme f the questis directed t the respdets may, fr istace, iquire it the "reass" fr previusly expressed piis, ad a cllecti f such reass may the be preseted t each respdet i the grup, tgether with a ivitati t recsider ad pssibly revise his earlier estimates. Bth the iquiry it the reass ad subsequet feedback f the reass adduced by thers may serve t stimulate the experts it takig it due accut csideratis they might thrugh iadvertece have eglected, ad t give due weight t factrs they were iclied t dismiss as uimprtat first thught (Ref 44, p 47). Decisi makig withi rgaizatis quite frequetly requires the type f expert pii that the Delphi methd has prve t be helpful i elicitig. Helmer ad Rescher pit ut that eve "i certai egieerig applicatis, particularly f relatively uderdevelped braches f physics, the reliace up 'kw-hw' ad expert judgmet is just as pruced as it is i the applicatis f plitical sciece t freig-plicy frmati." A example f this phemea is readily apparet i the desig ad maagemet f highway pavemet systems where stchastic variatis ecessitate the reliace prfessial experts t "supplemet the varius explicit elemets by apprpriate use f their capacities fr a ituitive appraisal f the may itagible factrs which critically affect the fial utcme" (Ref 44, pp 40-41). A idea which is widespread tday is that this type f decisi makig ca be aided by apprpriately desiged ifrmati systems. Hwever, whe dealig with cmplex prblems, such as pavemet maagemet where stchastic variati i the decisi variables is prevalet, the determiati f what is relevat data t iclude i a data base is t always clear. I fact the ucertaity, i what t iclude, creates a substatial dager because f the large capital utlay that is required t brig a MIS it existece. O the ther had it is this same ucertaity i the decisi variables that creates the greatest pprtuity fr the use f a MIS. If a prblem is clear cut, well defied, ad has explicit decisi variables, the there is little eed fr a data base type f ifrmati system. ppsite sides f the same ci whe csiderig a MIS. Dager ad pprtuity appear as A methd is eeded fr the desig f data bases that is mre certai tha flippig a ci that may eve be laded i favr f the dager side.

22 4 If data based ifrmati systems are t prve successful i supplyig ifrmati that will aid maagemet i makig ad implemet:1.g decisis, the the desig f the data structures f these data bases w:f.ll have t either cmplemet r icrprate the "kw-hw" ad expert judgmet f the preset decisi makers, wh are als the ptetial users f the syst.em. Theretically e shuld be mre capable f describig the ecess:ary data ctet f these data bases tha the preset decisi makers the~mselves, ad the Delphi Techique ffers a methd fr brigig abut a cver~;ece f this expert pii. Nt ly is a advatage gaied by brigig the expertise f the mst kwledgeable peple t bear the prblem, but als a add:f.tial rgaizatial behavir advatage ca be expected t accrue frm the applicati f a Delphi type methdlgy t the desig f a data base. ThiEl additial advatage ccurs because the ptetial users f the system al'e allwed t directly participate i its develpmet. Grup acceptace f a ifrmati system is critical t its effectiveess. Uless a ifrmat:f. system is used, there is way t justify the cst required t brig :f.t it existece. By participatig i the develpmet f the system, the grup's attitude tward the system is likely t imprve ad the prbability f the system beig used is, therefre, greatly icreased. Oe f the bjectives f the research effrt described i this reprt was t verify this expected :I.mprvemet i attitude as a result f participati i a Delphi desig f l:l data base. The Delphi Techique, which receives its ame frm the racle at Delphi i aciet Greece, has sice its icepti bee used by idmltry ad gvermetal agecies t frecast future techlgical develpmet~l. This future aspect f Delphi is felt by the authr t hld a sigificat ctati fr the applicati f the techique t the area f data base deelig. A data base requires a certai amut f time fr develpmet t the peratial stage after its desig has bee fialized. Eve after the dta base is peratial, the ifrmati system is cmmly used t assist with decisis that are made pssibly years after the system has reached the peratial stage. Thus the peple wh participate i the desig f a data base are i actuality attemptig t predict what types f data are likely t be eeded i future decisi makig. The Delphi Techique prvides a prve vehicle fr delvig it this type f ucertai ad pii lade questi.

23 5 This reprt will i part describe the develpmet f a Delphi methdlgy fr data base desig that prvides a user-desiger iterface thrugh which a determiati ca be made as t what the ctet f a ifrmati system shuld be. Csiderati will thus be give t the first ad third highest raked prjects i the Sciety fr Maagemet Ifrmati Systems' list f ptetial MIS research prjects. Cgitive Style The secd highest raked prject i the list f ptetial MIS research prjects is ccered with the characteristics f decisi makers which affect MIS system desig. Cgitive style, a persal characteristic f decisi makers, is a stable idividual preferece fr a particular "mde f perceptual rgaizati ad cceptual categrizati f the exteral evirmet. Oe particular style dimesi ivlves the tedecy t aalyze ad t differetiate the stimulus evirmet i ctrast t categrizatis that are based the stimulus as a whle." Sme peple "characteristically aalyze ad differetiate the stimulus field, applyig labels t subelemets f the whle. Others ted t categrize a relatively udifferetiated stimulus." Sme peple "are splitters, thers are lumpers" (Ref 92, p 74). It shuld be recgized that the splittig ad lumpig labels defie "ideal" types f behavir that represet the ed pits f a ctiuum. I reality we fid idividuals widely distributed alg the ctiuum; hwever, thrughut this reprt we will defie the idividual wh teds t lie relatively clser t the splittig ed f the ctiuum as havig a aalytical cgitive style while defiig the idividual wh lies clser t the lumpig ed f the ctiuum as havig a glbal cgitive style. The characteristic mde f cgitive fuctiig, with which the idividual appraches mst f his perceptual ad itellectual tasks, is believed t be a cmbied prduct f experiece ad educatial backgrud. Thus, the particular cgitive style f a idividual is slidified ver a lg perid f time ad is very difficult if t impssible t alter i aythig less tha mths f ccetrated effrt. "Idividuals ted t develp i a directi that is suited t sme prblem-types ad less effective with thers. Mature ad cmpetet adults geerally have a accurate sese f which situatis t seek ut ad which t avid. A particular cgitive style is either gd

24 6 r bad; its effectiveess depeds the ctext withi which the pers acts" (Ref 54, pi). Sme implicatis f the cgitive style factr fr ifrmati system desigers ca be fud i the results f recet research. Huysmas tested the impact f cgitive style differeces betwee the perat:ls researcher ad the maager the maagerial implemetati f peratis research recmmedatis, ad he ccluded that the cgitive style f the iteded user ca perate as a effective cstrait the implemetati f peratis research recmmedatis (Ref 46). Dktr ad Hamilt exteded the wrk f Huysmas by ivestigatig "the extet t which cgitive style differeces, as measured by writte tests f perceptual fuctiig, accut fr differetial acceptace rates f writte reprts with ctrastig presetati styles." They fud that differet reprtig sty14~s have differet acceptace rates by idividuals wh pssess a glbal r aalytical style. They claim that their results "highlight the ptetilil ifluece ad imprtace f icreased uderstadig f differetial thught prcesses i maagemet sciece implemetati" (Ref 27). Mas ad Mitrff i utliig "A Prgram fr Research Maagemet Ifrmati Systems" idetify the psychlgical type f the decisi maker as e f the key variables that cmprise a HIS. They discuss a persality typlgy that is similar t the cgitive style types alluded t i this reprt, ad they state that "what is ifrmati fr 4~ type will defiitely t be ifrmati fr ather." They have cmmeted that sciece has teded t be a predmiatly aalytical activity. "The :result is that the desig f HIS has teded t reflect this rietati f I:heir desigers, i. e., the desigers f HIS have teded t prj ect (r mistak4~) their dmiat psychlgical type (aalytical) t that f their cliets. The csequece has bee the almst ttal eglect f HIS desiged e:<pressly fr the glbal type."l Has ad Hitrff state that "there is a eed fr mre research this imprtat HIS variable" (Ref 63, pp ). lmas ad Mitrff call the aalytical type a Thikig-:>esati type ad the glbal type a Feelig-Ituiti type. This writer hiis replaced Thikig-Sesati i the qute with aalytical ad Feelig-Ituiti with glbal i rder t be csistet with precedig prtis f this reprt.

25 7 The statemet, that what is ifrmati fr e type will defiitely t be ifrmati fr ather, raises sme questis ccerig the applicati f a Delphi type methdlgy t the prblem f data base desig. Will the umber f data items, submitted by ptetial users fr iclusi i a data base, be a fucti f their particular cgitive style? Will a Delphi grup cmpsed slely f ptetial users wh have a particular cgitive style cverge t a data base desig that is sigificatly differet frm that btaied with a Delphi grup cmpsed slely f ptetial users with a differet cgitive style? Is the maer i which Delphi grups are structured, relative t cgitive style, likely t have a ifluece the data base desig achieved? Aswers t these questis was e f the primary bjectives f the research effrt that was carried ut i the ctext f actually applyig a Delphi type methdlgy t the desig f a highly cmplex, real life data base. Pavemet Feedback Data System (PFDS) Pavemet Feedback Data System (PFDS) is a applicati f the ccepts ad priciples f MIS t the maagemet f the highway pavemet system i the state f Texas. "I a setece, a PFDS is a autmated system ctaiig select feedback data frm actual i-service highway pavemets, t be used fr research, desig, ad maagemet fuctis" (Ref 83, p 6). The idea behid PFDS is t supplemet the pavemet decisi maker's judgmet by prvidig him with the best pssible ifrmati regardig the pavemet with which he is wrkig. By capturig ad strig data frm i-service pavemets as well as ew cstructi, a ivetry f the Texas pavemet etwrk ca be established i the frm f a cmputerized data base residet the Texas Highway Departmet (THO) System 370 i Austi. Usig the remte termials lcated i the District ffices thrughut the state, this ifrmati ca be fed back t District persel either i the frm f peridic ad evet triggered reprts r demad frm a query istigated at the District level. It is iteded that this ifrmati will supplemet the pavemet egieer's judgmet ad assist him i makig better pavemet decisis. Data frm the

26 8 imprved pavemets will be captured a ctiuig basis ad a iterative feedback lp established which will evetually result i a substatial imprvemet i the Texas highway etwrk. Figure 1 illustrates the scpe ad basic characteristics f the PFDS ccept (Ref 83, p 4). is what data shuld be captured ad stred i the data base. The questi Althugh the crerste f a Delphi type methdlgy fr data base desig is the fact that the ptetial users f the system determie the ctets f the data base, it is still pssible t establish a priri grss categries f data fr the purpse f illustratig the scpe f the system. j.detified: Fur majr categries, tgether with their sub-categries, ca be 1. Lcatial Data II. Desig ad Cstructi Data Maiteace Data III. Iput t the Pavemet Traffic Ladig Climatic Iput IV. Perfrmace Data It is ecessary t be able t accurately lcate a particular pit f iterest the highway etwrk ad the lcatial data serves this purpse. The desig ad cstructi data alg with its sub-categry f maiteace data specifies the state f the pavemet as it was built ad has bee maitaied. The iput t the pavemet, which csists f traffic ladig ad climatic iput the affects the maer i which the pavemet deterirates ver time. The fregig variables g tgether t determie the ridig quality f the pavemet, ad perfrmace data prvides measures f this variable. Figure 2 illustrates the iterrelatiship f the cmpets that make up the pavemet maagemet prblem (Ref 83, p 28). I essece the ed purpse f PFDS is t assist the pavemet egieer i predictig ad maagig pavemet quality whe faced with a exceedigly large umber f cmbiatis f pavemet variables. this purpse will be accmplished i tw ways: It is aticipated that (1) by immediately supplemetig the judgmet f the ptetial users i the field with accurate data, ad (2) by prvidig data i-service pavemets fr -gig research pavemet prblems. The first use f PFDS parallels the traditial MIS

27 Updated DesiC) ) Mcd~:s Request fr Radm Data Retrieval t Prgrams Texas HiC)hwOYI Oaia ClleGti a StrQe PrClrrs Output:.. ved Mde"') I Rutie Reprt(s) P=f(..... t...). I Special Reprt(s) I Evet-TriQQered I Reprt(s) A Iterative Prcess Fig 1. Scpe f a pavemet feedback data system (PFDS) (after Strm et a1, Ref 83).

28 Temperature... Raifall , I L Other Variables -L. i-_------fiji, Climate AADT Weighted Evirmetal Fetr Lad Grups Equivalecy Factrs r , I Other Variables L.. -.l Traffic Equivalets Pavemet Perfrmace System Service Ufe Cstructi. Materials Maiteace Pavemet / Pavemet Stregth Overlays r , I Recstructi L J Fig 2. Cmpets f pavemet perfrmace (after Strm et ai, Ref 83).

29 11 apprach, while the secd use f PFDS is aalgus t usig the highway system as a research labratry. With such a labratry available, mre precise idetificati ad quatificati f the iterrelatiships amg pavemet variables is prbable, ad this added kwledge shuld fuel the develpmet f mre refied cmputer mdels fr pavemet aalysis. Thus PFDS is evisied as havig mre tha e type f user ad mre tha e fucti. It is iteded that, whe peratial, PFDS will be used by three distict grups withi the THD, each f which "will have a differet type f ifrmati eed: (1) the District Egieer ad his staff, (2) the admiistrative headquarters ad divisis, ad (3) researchers" (Ref 83, p 85). Withi the abve metied research categry, it is aticipated that PFDS will als be used by the THO's tw cperatig research istitutis, Texas Trasprtati Istitute (TTl) ad Ceter fr Highway Research (CFHR). I additi t beig accessed ad updated by a diverse grup f users, it is expected that PFDS will prvide ifrmati fr use i several fuctial areas, such as: (1) Desig (2) Maiteace (3) Admiistrati, ad (4) Research. I this respect the PFDS data base is viewed as beig a truly "cmm" data base, ad it is felt that the Delphi methdlgy prpsed herei ffers a meas fr vercmig sme f the may prblems iheret i desigig a cmm data base i a cmplex situati such as PFDS. Oe f the ptetial prblems a ifrmati systems' desiger faces i attemptig t develp a cmm data base like PFDS is the pssibility f verlkig the ifrmati eeds f a imprtat segmet f the ptetial users r eve wrse missig the real eeds f the etire grup. A Delphi type methdlgy requires the ivlvemet f the ptetial users f the system, ad assurace is thus btaied that their eeds have bee csidered. Examiatis f the effrts f tw ther states i develpig ifrmati systems similar t PFDS, reveal ther advatages fr the applicati

30 12 f the Delphi techique t the desig f the PFDS data bas.~. The Wiscsi Departmet f Trasprtati desiged ad built their Highway Netwrk Data ad Ifrmati (HNDI) System lalcgely idepedet f a specific grup f users. Whe the system became peratial, they fud that user really existed ad that the ext.~cessary step was thrugh idctriati f field persel as t the Hcpe, character, ad pssible users f HNDI (Ref 83, p 8). Idetificati f ptetial users ad their idctriati as t the scpe ad character f the system are itegral steps i the Delphi prcess f data base desig. Therefre, the prblems faced by Wiscsi i attemptig t implemet HNDI are autmatically elimiated by use f the Delphi techique. I additi, the participats i the Delphi prcess receiv.~ valuable traiig that is expected t facilitate their use f the system whe it reaches the peratial stage. Miller ad Barrett while describig the implemetati f the Flrida Departmet f Trasprtati's (FOOT) Multiprject Schedu1:lg System (MPSS) cauti that it is imprtat t avid "the appearace f smethig ew beig 'rammed dw the thrats' f the users." They state that Quite the ppsite feeligs ca be evked by brigig the users bard ad givig them a strg vice i the system debig prcess. This is e area where the FDOT's desig prcedure culd have bee imprved. Sme cmplaits f MPSS system users were eetered arud the fact that the MPSS did t adequately fill their eeds ad it was smethig beig frced up them which they had ctrl ver. This implies a certai amut f resetmet due t -participati i the plaig prcess (Ref 69, p 19). Eve thugh Miller ad Barrett have failed t prvide expl:lcit istructis fr a methd that allws the participati they advcate, :It is felt that the Delphi methdlgy emplyed i the desig f the PFDS data base adequately accmplishes the spirit f their prpsal. By hav:lg 241 ptetial users frm the THD, TTl, ad CFHR take part i the Delphi prject t desig the PFDS data base, it is aticipated that the FOOT's diff:lculties with implemetati prblems due t -participati will be avided. As was previusly metied, a further check the Miller-Barretl: prpsal was prvided sice e f the bjectives f the PFDS desig prject was t determie hw the attitude f the ptetial users chaged as a result f participatig i the data base desig prcess.

31 13 Ratiale ad Limitatis Heretfre, the data ctet f data bases has geerally bee determied by the systems aalyst wh has traditially emplyed a variety f techiques i arrivig at hi8 appraisal f what data items the data base shuld ctai. These techiques iclude, amg thers, iterviews with the ptetial users, decisi level aalysis, ifrmati flw aalysis, ad iput/utput aalysis. The specific techique r cmbiati f techiques that the aalyst applies i ay give situati is rmally depedet up the aalyst's judgmet ad persal prefereces. Thus, up util w, there has bee a table lack f systematic prcedures fr determiig what the ctet f a data base shuld be; ad this lack has created the ptetial fr sme serius prblems resultig frm the pssibility f aalyst bias. By applyig the systematic Delphi prcedures, the pprtuity fr the ecrachmet f aalyst bias it the data base desig is elimiated. I place f this bias, the Delphi prcess prvides a frum fr the expressi f may seperate views regardig the data requiremets. These views are prvided by the differet disciplies that are brught t bear each data item. Fr example, i the desig f the PFDS data base the separate fuctis f Desig, Maiteace, Research, etc. all prvided differet prespectives i the csiderati f each data item. It is thrugh the may separate views which Delphi brigs t the prblem that the validity f the data ctet is guarateed. The validity f the data ctet is guarateed either thrugh the agreemet f the ptetial users r thrugh the debate that takes place whe the ptetial users are iitially i disagreemet. The first type f guaratr is kw as a Katia Iquirig SY8tem ad the secd type is kw as a Hegelia Iquipig System (Ref 63, pp ). Bth types f guaratrs are well suited fr ill-structured prblems; ad as we have previusly see, mst data base systems are desiged t cpe with prblems f a ill-structured ature. A data base, i rder t be effectively utilized, has t fit r match the separate wrld views held by each f its users. The Delphi prcess ideally prvides the iteracti that is ecessary t brig abut the required sythesis f the separate perceptis held by each f the ptetial users. A priri it is better that this sythesis be achieved befre

32 14 th~ system is peratial. Thus, theretically, the Delphi prcess practically guaratees a better data base desig tha culd be achieved by a systems aalyst. Furthermre, the Delphi prcess appears t be suitable t a wide rage f data base desig situatis. Althugh Delphi appears t be applicable t a wide r~lge f data base desig situatis, there are prbably limits as t hw dee~ply ivlved the ptetial users ca be expected t becme i the desig pi'cess. It is therized that the degree f successful ivlvemet is depedet the amut f educati ad experiece the ptetial users have had with data base systems prir t the desig f the data base i questi. After the establishmet f the bjectives t be met by a ew system, the steps i desigig the data base are rughly: (1) idetificati (if ifrmati eeds ad determiati f hw the ifrmati is t be cllected, ad (2) classificati f data items ad develpmet f the da.ta structure. Step 1 culd be csidered t be f a -techical ature:, i terms f the ptetial user's view f the data base desig prcess, while Step 2 culd be csidered mre f a techical ature. It is expected that Step 1 ca be easily cmpleted by the ptetial users; hm,'ever, Step 2 may ffer mre difficulty uless the ptetial users have bee previusly acquaited with data base ccepts. Fr example, i the PFDS data base desig prject, which will be described i subsequet chapters, the ptetial users were t previusly familiar with data, base desig ccepts; ad trial effrts t slicit their help i e area f Step 2 prved t be futile. Util further research ca be cducted with ptetial users wh have had sme previus experiece with data bases, it shuld be cservatively assumed that the Delphi methdlgy is limited t the -techical prti f the data base desig prcess. Verificati f Delphi's ptetial i the -techical area f data base desig was e f the research bjectives f the study that will be described i subsequet chapters. Summary f Research Objectives Sice the research effrt described i this reprt cvers several specific bjectives withi the ctext f e experimetal desig, the

33 15 fllwig summary f the research bjectives is icluded fr the cveiece f the reader: (1) T verify the applicability f a Delphi type methdlgy t the prblem f data base desig by utilizig the methd t determie what the ctets f the PFDS data base shuld be; (2) T determie what ifluece, if ay, cgitive style is likely t have i a Delphi type methdlgy fr data base desig; ad i particular t determie: (a) if the iitial umber f data items submitted by ptetial users is a fucti f their cgitive style, (b) if a Delphi grup cmpsed slely f participats with e cgitive style will cverge t a data base desig differet frm that f a Delphi grup with participats wh have a differet cgitive style, ad (c) if the maer i which Delphi grups are structured, relative t cgitive style, is likely t have a ifluece the data base desig achieved; ad (3) T verify the theretical assumpti that the attitude f the participats tward the system will imprve as a result f their participati i the data base desig prcess. Scpe f the Reprt This reprt describes a research ivestigati cducted t determie the ifluece f cgitive style i a Delphi methdlgy as it was applied t the desig f the PFDS data base. Theretically the Delphi techique hlds great prmise fr vercmig sme cmm prblems faced by the ifrmati system desiger. By prvidig a suitable user-desiger iterface the methd allws the ptetial users t determie what the ctets f their data base shuld be. I additi, participati i the develpmet f the system is expected t brig abut a imprved attitude the part f the users tward the system. Verificati f this ptetial, whe the methd is actually applied i the ctext f desigig a cmplex, real-life data base was e f the primary bjectives f the research effrt that is reprted i the fllwig chapters. Chapter 2 presets a review f the literature, the Delphi ad cgitive style ccepts, that is pertiet t the applicati f these ccepts t the area f data base desig.

34 16 Chapter 3 discusses the mdificatis t Delphi that,~re required i rder t apply the methd t the area f data base desig. The PFDS example is used t demstrate the methdlgy, ad a cmpl~ter prgram fr prcessig the Delphi ifrmati flws assciated with a data base desig effrt is described. Chapter 4 presets the hyptheses f the study ccerl1ig cgitive style ad participati. The chapter the describes the e:~perimeta1 desig which was used as a meas f gatherig the data t test these hyptheses. Chapter 5 discusses the criteria used i selectig th,a measuremet istrumet fr umerically assessig the cgitive style f the participats, ad it describes the mdificati f a attitude scale that was used t measure the participats' attitudes tward the system. Chapter 6 aalyzes the relatiship that was discver ad betwee the participats' cgitive styles ad their ability t articulate data items. Chapter 7 presets a statistical methd fr testig the hypthesis that Delphi grups cmpsed f members with differet cgitive styles will cverge t differet data base desigs. The results btaied frm applyig this test t the data gathered i the PFDS prject are discussed. Chapter 8 reprts the ivestigatr's subjective pii'~s, impressis, ad bservatis f the Delphi prcess; ad qualitative differeces, betwee the data base desigs f differet cgitive style grups, that were bserved i the PFDS prject are discussed. Chapter 9 examies the effect that participati i t:e PFDS data base desig prcess had the attitude f the participat.s tward the system ad their participati i its develpmet. Chapter 10 presets the cclusis f the study a1:~ with recmmedatis as t methds fr applyig the Delphi techique t the area f data base desig. Ccmittat1y recmmedatis are preseted ccerig further research that wuld be beeficial i gaiig additial uderstadig f the methdlgy.

35 CHAPTER 2. REVIEW OF THE LITERATUi.E I this chapter a review f the literature the Delphi Techique ad Cgitive Style will be udertake. I this review a brief histry, tracig the evluti f the tw ccepts, will be preseted, eve thugh a attempt will be made t ccetrate primarily thse aspects f the tw ccepts that are pertiet t the use f the Delphi Techique as a methd fr data base desig. The prcedures that are rmally fllwed i admiisterig the Delphi Techique will be reprted i rder t btai a clearer uderstadig f what, if aythig, is likely t be sacrificed by mdifyig the techique fr use as a user-desiger iterface t determie what the ctets f a data base shuld be. The cgitive style ccept is relatively ew ad as such is t yet cmpletely ecmpassed withi e uifyig thery. There are may diverse dimesis t the ccept, ad this literature review will examie sme f these dimesis i rder t prvide a fudati fr the selecti f a dimesi that is relevat t the task f data buse desig. Delphi "Prject Delphi" is a itermittet but gig effrt f the Rad Crprati which is "ccered with the prblem f usig grup ifrmati mre effectively. The early studies were ccered maily with imprvig the statistical treatmet f idividual piis. I 1953, Dalkey ad Helmer itrduced a additial feature, amely iterati with ctrlled feedback. The set f prcedures that have evlved frm this wrk has received the ame Delphi" (Ref 19, p 20). "Its bject is t btai the mst reliable csesus f pii f a grup f experts. It attempts t achieve this by a series.f itesive questiaires iterspersed with ctrlled pii feedback." The techique "ivlves the repeated idividual questiig f the experts (by iterview r questiaire) ad avids direct cfrtati f the experts with e ather" (Ref 22, p 458). 17

36 18 By bviatig the ecessity fr face-t-face discussi, which is the traditial way f plig idividual piis, Delphi is able t circumvet sme serius difficulties that are iheret i face-t-face iteracti such as cmmittee meetigs. iclude: The mst serius f these difficulties prbably (1) The spurius ifluece f a high status idividual the grup- here the status f a idividual, which is fte urelated t his expertise the questi at had, is give udue csiderati i a face-t-face discussi. (2) Eg cmmitmet--after pely cmmittig himself t a particular psiti, the idividual is less likely t respd t facts ad piis advaced by ther members f a face-t-face discussi grup. (3) Grup pressure fr cfrmity--i a face-t-face situati the idividual ecuters great pressure t jump the badwag ad ji the grup. Delphi's elimiati f the disadvatages iheret i a face-t-face ecuter allws a grup t reach a less emtial ad mre reased csesus f pii. It is presetly stadard prcedure t have e r tw systems aalysts develp a data base desig; ad this traditi, f avidig the direct ivlvemet f a large umber f the ptetial users prbably stems i part frm the prblems iheret i face-t-face ecuter. Delphi ffers a meas f avidig the prblems assciated with face-t-face ecuter, but the primary questi is ca aythig be gaied by brigig mre peple it the prcess. Dalkey idicates that the aswer shuld prbably be i the affirmative. He pstulates what he calls the "-heads rule," Le. heads are better tha e. He states The basis fr the -heads rule is t difficult t fid. It is a tautlgy that, ay give questi, there is at least as much relevat ifrmati i heads as there is i aye f them. O the ther had, it is equally a tautlgy that there is at least as much misifrmati i heads as there is i e. Ad it is certaily t a tautlgy that there exists a techique f extractig the ifrmati i heads ad puttig it tgether t frm a mre reliable pii. With a give prcedure, it may be the misifrmati that is beig aggregated it a less reliable pii. The -heads rule, the, depeds up the prcedures.whereby the heads are used. Dalkey ges t pit ut that i the case f umerical estimates, the prbability that the media is at least as clse t the true aswer as ay idividual respse is at least e half; fr the mea, the errr f the mea (measured by the distace t the true aswer)

37 19 is less tha r equal t the average errr f the idividual aswers. These tw criteria are t equivalet, ad fr differet decisi situatis e r the ther culd be mre apprpriate (Ref 19, p 16). A set f experimets was cducted, at Rad, t examie the "depedece grup size f the mea accuracy f a grup respse" (Ref 19, p 17). Figure 3, frm a Rad paper by Dalkey et ai, presets the data btaied frm these experimets. The data was develped frm a large set f aswers grups gave t factual questis where the aswers were kw t the experimeter but t the subjects. "The curve was derived by cmputig the average errr f grups f varius sizes where the idividual aswers were draw frm the experimetal distributi.--the grup errr is the abslute value f the atural lgarithm f the grup media divided by the true aswer." Dalkey cmmets that It is clear frm the figure that with this ppulati f aswers, the gais i icreasig grup size are quite large. It is iterestig that the curve appears t be decreasig i a defiite fashi, eve with grups as large as twety-ie. This was the largest grup size we used i ur experimets (Ref 19, p 17). I discussig the use f this data fr determiig what cstitutes a substatial size grup i regard t expected accuracy, Dalkey et al state that the apprpriate size "is t sharply determied by the curve." They "selected 7 as the lwer limit the gruds that it was rughly i the middle f the 'kee' f the curve" (Ref 20, p 6). Dalkey brigs ut ather facet f the ifluece f grup size whe he discusses reliability. Ather imprtat csiderati with respect t the -heads rule has t d with reliability. The mst ucmfrtable aspect f pii frm the stadpit f the decisi maker is that experts with apparetly equivalet credetials (equal degrees f expertess) are likely t give quite differet aswers t the same questi. Oe f the majr advatages f usig a grup respse is that this diversity is replaced by a sigle represetative pii. Hwever, this feature is t particularly iterestig if differet grups f experts, each made up f equally cmpetet members, cme up with highly differet aswers t the same questi. Usig the same data btaied i the experimets accuracy as a fucti f grup size, a curve was cstructed by the Rad grup which shws the relatiship betwee reliability ad grup size. This curve is reprduced i Figure 4.

38 "" Q :I 0... C) CJ CJ > ct OJ ~----~----~ ~~~-r--'--~i----~i Number i grup Fig 3. Effect f grup size (after Dalkey et B,l, Ref 20).

39 c ;; I O~ ~------~~ r------~------~ II 13 Number i Grup Fig 4. Reliability vs. grup size (after Da1key, Ref 17).

40 22 It was cstructed by selectig at radm pairs f grups f respdets f varius sizes ad crrelatig the media respses f the pairs twety questis. The rdiate is the average f these crrelatis. It is clear that there is a defiite ad mtic icrease i the reliability f the grup respses with icreasig grup size. It is t clear why the relatiship is apprximately liear betwee =3 ad =ll. I cmmetig the results f these experimets Dalkey ccludes that "i the area f pii, the, the -heads rule appears t be justified by csideratis f bth imprved accuracy, ad reliability" (Ref 19, pp 18-19). This ifrmati the effect f grup size will be referred t i Chapter 4 which develps the experimetal desig fr testig hyptheses regardig the ifluece f cgitive style i the data base desig prcess. The 1953 study, i which Dalkey ad Helmer iitially itrduced the feature f iterati with ctrlled feedback, is iterestig bth frm a histrical perspective ad als fr the may facets f the techique that it presets. "The experimet was desiged t apply expert pii t the selecti, frm the viewpit f a Sviet strategic plaer, f a ptimal U.S. idustrial target system ad t the estimati f the umber f A-bmbs required t reduce the muitis utput by a prescribed am<>ut" (Ref 22, 458). Seve experts participated, respdig t five questi.)aires submitted at apprximately weekly itervals. The first questiaire was fllwed by a iterview i which each respdet was asked t reprduce the reasig by which he arrived at a estimate f the umber f bmbs ad t shw the cmpet breakdw by idustries. The third als was fllwed by a iterview fr the clarificati f ambiguities. The chices f target systems were quit,~ distict, the ly cmm feature beig the iclusi f the steel idustry i each. The umerical quatity beig estimated shwed,:siderable cvergece. The rati betwee the largest ad small est respse was abut 100 t 1 the iit ial rud but had drppl~d t abut 3 t 1 the fial rud (Ref 6, p 9). This example illustrates three f the basic features f Delphi: "(1) Aymity. The piis f the grup are recrded separat4~ly--usually by questiaire--ad whe cmmuicated t ther members f t;le grup are t attributed t specific idividuals. (2) Ctrlled fe4adback. A exercise is cducted i several ruds i which the pii.)s geerated durig e rud are fed back t the grup the ext rud, usually i

41 23 the frm f statistical summaries. (3) Statistical grup respse. The 'grup pii' is expressed i terms f a statistical scre--the media f fial respses has prved t be mst suitable fr umerical estimates. There is pressure t arrive at a 'csesus'lt (Ref 18, p 4). Aymity, effected by the use f questiaires r ther frmal cmmuicati chaels, such as -lie cmputer cmmuicati, is a way f reducig the effect f dmiat idividuals. Ctrlled feedback- cductig the exercise i a sequece f ruds betwee which a summary f the results f the previus rud are cmmuicated t the participats--is a device fr reducig ise. Use f a statistical defiiti f the grup respse is a way f reducig grup pressure fr cfrmity; at the ed f the exercise there may still be a sigificat spread i idividual piis. Prbably mre imprtat, the statistical grup respse is a device t assure that the pii f every member f the grup is represeted i the fial respse. Withi these three basic features, it is, f curse, pssible t have may variatis. There are several prperties f a Delphi exe~cise that shuld be pited ut. The prcedure is, abve all, a rapid ad relatively efficiet way t ltcream the tps f the heads" f a grup f kwledgeable peple. I geeral, it ivlves much less effrt fr a participat t respd t a well-desiged questiaire tha, fr example, t participate i a cferece r t write a paper. A Delphi exercise, prperly maaged, ca be a highly mtivatig evirmet fr respdets The feedback, if the grup f experts ivlved is mutually selfrespectig, ca be vel ad iterestig t all. The use f systematic prcedures leds a air f bjectivity t the utcmes that mayr may t be spurius, but which is at least reassurig. Ad fially, aymity ad grup respse allw a sharig f respsibility that is refreshig ad that releases t~ respdets frm scial ihibitis (Ref 19, p 21). Ather aspect f Delphi that is demstrated i the U.S. idustrial target system example is the methd's ability t cme t grips with prblems that ivlve ucertaity ad value judgmets. Dalkey states that "i thse cases where a grup f kwledgeable idividuals reprts a wide diversity f pii, it wuld seem that i the majrity f cases e kws the aswer. I fact, the diversity f pii is a relatively gd measure f the degree f lack f kwledge ccerig the questi.". The first basic csiderati i the Delphi apprach, the, csists i recgiti f the high degree f ucertaity that surruds imprtat questis--especially questis with value ctet--ad relaxig the desire t fid the s-called right aswer. It the becmes meaigful t ask hw the diversity f ifrmati that leads t disagreemet withi the grup ca be amalgamated t lead t the best available aswer t the questi. Actually, eve this weaker

42 24 aim is t strg at preset. There are may features f the judgmetal prcess which we uderstad t prly t defie best, much less specify practical rules fr attaiig it. At pr,aset we are limited t rules fr fidig better aswers t ucertai questis (Ref 19, p 4). Sice a data base is custmarily used at sme future time, by sme udetermied grup f peple, as a aid i makig sme as yet uspecified decisi; ucertaity is iheret i ay attempt t determie 'Jhat the ctets f the data base shuld be. As will becme clearer whe t":te cgitive style ccept is reviewed i greater detail later i this,::hapter, there are als iate differeces f pii r differet value judgmets amgst differet users as t what types f ifrmati may be imprtat eve if all f the abve ucertaities were cmpletely specified. If the Delphi apprach is i fact capable f prducig better aswers thii ther kw methds whe dealig with prblems ivlvig ucertaity ad value judgmets, this is a sigificat recmmedati fr the csiderati f the use f the techique as a methd fr data base desig. Thrughut the remaider f this secti, which reviews the literature Delphi, evidece will be preseted that will udubtedly lead the reader t cclude that such a recmmedati is ideed warrated. I rder t ivestigate the questi f whether "the use f iterati ad ctrlled feedback have aythig t ffer ver the Iml~ref statistical aggregati f piis,1i a extesive series f experimets has bee cducted at Rad. A secdary bjective f these experimets was lit get sme measure f the value f the prcedures, ad als t 'tai, as a basis fr imprvig the prcedures, sme isight it the ifrmati prcesses that ccur i a Delphi exercise." I discussig e set f these experimets Da1key has stated that We used upper-class ad graduate studets, primarily frm UCLA, as subjects. They were paid fr their participati. Fr subject matter we chse questis f geeral ifrmati, f the srt ctaied i a almaac r statistical abstract. Typical questis were: "Hw may telephes were i use i Africa i 1965?" "Hw may suicides were reprted i the U.S. i 1967?" "Hw may wme maries were there at the ed f Wrld War II?" This type f material was selected fr a variety f reass: (1) we wated questis where the subjects did t kw the aswer but had sufficiet b,ackgrud ifrmati s they culd make a ifrmed estimate; (2) w': wated questis where there was a verifiable aswer t check tha perfrmace f

43 25 idividuals ad grups; ad (3) we wated questis with umerical aswers s a reasably wide rage f perfrmace culd be scaled. As far as we ca tell, the almaac type f questi fits these criteria quite well. There is the questi whether results btaied with this very restricted type f subject matter apply t ther kids f material. We ca say that the geeral-ifrmati type f questi used had may f the features ascribable t pii: amely, the subjects did t kw the aswer, they did have ther relevat ifrmati that eabled them t make estimates, ad the rute frm ther relevat ifrmati t a estimate was either immediate r direct. The geeral utcme f the experimets ca be summarized rughly as fllws: (1) the iitial rud, a wide spread f idividual aswers typically esured; (2) with iterati ad feedback, the distributi f idividual respses prgressively arrwed (cvergece); ad (3) mre fte tha t, the grup respse (defied as the media f the fial idividual respses) became mre accurate. This last result, f curse, is the mst sigificat. Cvergece wuld be less tha desirable if it ivlved mvemet away frm the crrect aswer (Ref 19, pp 21-22). I discussig this same set f experimets, i a differet referece, Da1key has made the additial cmmet that the priciple decrease i the spread f piis ccurs betwee the first ad secd ruds, ad he states We have ccetrated the clsed ifrmati case; i.e., durig the exercise, ew ifrmati ccerig the subject matter is itrduced it the grup. Eve i this case, the accuracy f the grup respse icreases with iterati--rather like liftig itself by its lgical btstraps the part f the grup (Ref 18, p 5). I rder t extraplate the fidigs f the abve described set f experimets that dealt with factual data, i.e. almaac type questis, t the area f pii ad value judgmets; the Rad grup established three cditis "as a partial defiiti f the term grup judgmet fr value questis." (I) ReasabLe distributis. If the distributi f grup respses a give umerical value judgmet is flat, idicatig grup idifferece, r if it is U-shaped, idicatig either that the questi is beig iterpreted differetly by tw subgrups, r there is a actual differece f assessmet by tw subgrups, the it seems iapprpriate t assert that the grup csidered as a uit has a judgmet that questi. (2) Grup reliability. Give tw similar grups (e.g., tw grups selected ut f a larger grup at radm) the grup judgmets a give value questi shuld be similar. Over a set f such value judgmets, the crrelati fr the tw subgrups shuld be high.

44 26 (3) Chage, ad cvergece iterati with feedbac;~. This cditi is prpsed i part by aalgy with result:; frm experimets with factual material, that is, shifts f idivid:jal respses tward the grup respse ad reducti i grup variability. Mre geerally, if members f the grup d t uti.lize the ifrmati i reprts f the grup respse earlier ruds whe geeratig respses later ruds, it seems iapprpriate t csider these respses as judgmets. The Rad grup the, i ather set f experimets, applied the three criteria "t value judgmets by uiversity studets ccerlig the bjectives f a higher educati ad the bjectives f everyday (idividual) life." The studets geerated a list f bjectives fr these tw areas, ad rated them a scale f relative imprtace. Three differet ratig methds were emplyed i rder t test bth grup reliability ad stability ver scalig techique. Ratigs were btaied each f tw ruds, where the results f the first rud (the media ad upper ad lwer quartiles f the respses) were fed back betwee ruds. The data geerated by the value judgmets satisfied the three criteria t abut the same degree as crrespdig data frm similar grups makig factual estimatis. I shrt, the utcme f these experimets appears t be that the Delphi prcedures--as far as we ca evaluate them at preset--are apprpriate fr geeratig ad assessig value material (Ref 19, p 57). I a series f experimets cducted by Rbert M. Campbell (Ref 10) the Delphi Techique was cmpared t traditial methds f itegratig grup pii. busiess frecastig at UCLA. it tw grups. Campbell used studets frm tw graduate semiars i The tw sectis were each radmly divided Oe grup f studets frm each f the tw sectis were asked t predict sixtee ecmic idicatrs a quarter i advace. The tw grups were allwed t iteract freely amgst themselves ad use ay methds they felt apprpriate i arrivig at a grup estimate. grups were desigated as the traditial grups. These tw The remaiig tw grups were als asked t predict the same idicatrs, but were required t use the Delphi prcess i makig their predictis. Fur ruds f the Delphi prcess were cducted ver a six week perid, ad i thirtee cases the Delphi prcess prved t be mre accurate. The rmal frecastig techiques, carried ut i the ctext f face-t-face iteracti, were mre accurate i ly tw cases. highly favrable result (Ref 19, p 24). Similar studies at Rad have cfirmed this

45 27 I the case f data base desig we are t ly ccered with perfectig a methd that will tap the expertise f the mst kwledgeable peple, i.e., the ptetial users, but we are als ccered with the pssible effect that such participati may have the attitude f the users tward the system. I this vei, Dalkey cmmets that he believes the features f a Delphi exercise are desirable especially "where grup acceptace is a imprtat csiderati" (Ref 19, p 21). I ather istace he says I ca state frm my w experiece, ad als frm the experiece f may ther practitiers, that the results f a Delphi exercise are subject t greater acceptace the part f the grup tha are the csesuses arrived at by mre direct frms f iteracti (Ref 17, p 17). The self ratig aspect f the Delphi methd is als wrthy f brief meti because it is used i the Delphi type methdlgy fr data base desig that is prpsed i the ext chapter. self-ratig ccept. Olaf Helmer discusses the A refiemet which has already bee successfully tested is that f attributig differetial weights t the piis f differet experts. Clearly, if it were easy t measure the relative trustwrthiess f differet experts, we wuld give greatest weight t the piis f thse wh are mst trustwrthy. I the absece f bjective measuremets t this effect, we have examied the pssibility f relyig istead the experts' subjective self-appraisal f their w cmpetece, ad fud this quite prmisig (Ref 43, p 7). I additi t prvidig the rdiary ifrmati required by the Delphi prcess, the participats are als asked t rak the items uder csiderati with respect t the cmpetece that they have i makig their judgmet. This rakig is best thught f as a idex f self-cfidece r self-rated cmpetece i regard t each particular item. The Rad experimets alluded t by Helmer required each participat t prvide a selfratig, "based a scale f 1, 2, 3, r 4," which idicated "a evaluati f his w degree f expertise each questi" (Ref 7, p 4). The, istead f usig the media as the grup csesus, as is cmm at Rad, "ly the respses f thse idividuals were take wh had raked their cmpetece regardig that idex relatively mst highly; ad the media f just these frecasts was the used as the grup csesus. It subsequetly tured ut that this select media, cmpared t the media f all

46 28 respses, was clser t the true value i tw thirds f the cases" (Ref 43, p 8). Examiati f the varius aspects f the Delphi prc,~ss, that are reviewed abve, led this writer t cclude that a Delphi type methdlgy is, i thery, highly suited t the prblem f data base d,~sig. remaiig chapters i this reprt discuss a experimet, t test this thery, that was cducted withi the ctext f applyig Delphi t the desig f a highly cmplex, real life data base. the participats i a data base desig prcess was viewed,~s The The cgitive style f beig a pssible factr that might ifluece the maer i which Delphi grups shuld be structured; therefre, the ext secti f this review '~xamies cgitive style ccept. the Cgitive Style Mi chael Wallach cmmets that "the wrd style has ete,red psychlgy's techical vcabulary t sigify certai kids f geerality--that smee wh reacts i e maer i e situati will react i a particular characteristic way i ather" (Ref 67, p 199). Thus, the desigati cgitive style refers t the applicati f the style ccept t idividual csistecies i certai cgitive areas, such as percepti ad itellectual fuctiig. By ccetratig the perceptual rgaizati ad adaptati aspects f cgitive fuctiig, it is pssible t geerate a defiiti f cgitive style germae t the cetral fcus f this study, 1. e. the desig f data bases fr ifrmati systems. Cgitii)e style ca be defied, fr ur purpses, as the self csistet maer ill which a idividual extracts ifrmati frm his evirmet ad uses this ifrmati i his prblem slvig ad decisi makig activities. Sme f the pssible implicatis that cgitive styll~ hlds fr the desig f ifrmati systems ca be fud i the wrk f Huysmas ad als i the wrk f Dktr ad Hamilt that were referred t briefly i Chapter 1. Huysmas cducted a labratry experimet i which he ivl~stigated the factrs that ifluece maagerial implemetati behavir i regard t peratis research recmmedatis. I particular he was ccered with "the differece i cgitive styles betwee maager ad p,aratis researcher" (Ref 46, p 92). Huysmas' experimet was cducted i "tha frmat f a

47 29 busiess game i which e 'presidet' ad fur 'maagers' made fiacial, pricig, prducti, ad purchasig decisis fr a hypthetical firm durig several 'decisi perids'" (Ref 46, p 94). The fur maagers, whse rles were simulated, preseted advice t the presidet wh was slely respsible fr makig the decisis fr the firm. The presidet's rle was the ly rle filled by a experimetal subject. These subjects were selected frm MBA studets at the Uiversity f Califria at Berkeley. The experimetal subjects were classified it the tw categries f aalytic r heuristic accrdig t their predmiat ways f reasig. The aalytic type "reduces prblem situatis t a cre set f uderlyig causal relatiships. All effrt is directed twards detectig these relatiships ad maipulatig the decisi variables (behavir) i such a maer that sme 'ptimal' equilibrium is reached with respect t the bjectives. A mre r less explicit mdel, fte stated i quatitative terms, frms the basis fr each decisi." The heuristic type "emphasizes wrkable slutis t ttal prblem situatis. The search is fr aalgies with familiar slved prblems rather tha fr a system f uderlyig causal relatiships, which is fte thught illusry. Cmm sese, ituiti, ad uqualified 'feeligs' abut future develpmets play a imprtat rle t the extet they are applied t the ttality f the situati as a rgaic whle, rather tha as built up frm clearly idetifiable separate parts. It is extremely difficult, if t impssible, t ucver the mechaisms that lead t a decisi uder hueristic reasig. The resultig decisi, hwever, ca be characterized by its emphasis csistecy with its iteral ad exteral evirmet i ctrast with the decisi f a aalytic reaser which emphasizes ptimality" (Ref 46, pp 94-95). The experimetal subject, wh was uaware f the true ature f the research effrt, was preseted with a peratis research recmmedati based "a exteded versi f the 'ewsby' prblem" which was applicable t the decisis the hypthetical presidet was beig asked t make. recmmedati was t idetified as a peratis research prpsal. Tw differet implemetati strategies--e aimed at gaiig the subject's "explicit," the ther at gaiig his "itegral," uderstadig f the peratis research prpsal--were expressed thrugh tw versis f the simulati rules that gvered the accutig maager's cmmuicatis. Bth versis ctaied sufficiet ad similarly The

48 30 preseted argumets t eable the "presidet" t gai a geeral appreciati fr, ad a itegral uderstadig f, the ref;earch de. The ly essetial differece betwee the versis csisted f the iclusi f frmulas t supprt the research fidigs whe the "exp1icituderstadig" apprach was used (Ref 46, p 96). "A subject's adpti/rejecti behavir with respect t the OR recmmedatis was measured largely the basis f his marketig ad prducti decisis" (Ref 46, p 96). It was fud that aalytic subjects reached a higher degree f implemetati tha heuristic subjects whe the accutig maager used the "explicit-uderstadig" apprach i presetig the peratts research prpsal. It was als fud that the heuristic ad aa1yttc subjects wh received the "itegral-uderstadig" apprach reached a higher degree f implemetati tha the heuristic subjects wh received the "exp1icituderstadig" apprach. Frm the results f this research, Huysmas ccluded that (a) Cgitive style may perate as a effective estrait the implemetati f peratis research recmmedatis (b) The peratis researcher may achieve implemetati by takig this implemetati cstrait it accut i his research strategy (c) Whe the cgitive-style prpesities f pel=atis researcher ad maager d t agree, the maager may discard the peratis researcher cmpletely as a surce f ifrmati: A research recmmedati will t be implemeted matter hw persuasive ad ituitively appealig the peratis researcher's argumets may be, simply because the maager has serius iteti f csiderig it i the first place (Ref 46, p 101). Fllwig the lead f Huysmas, Dktr ad Hamilt cducted a experimet "t examie the effects f cgitive style the maagerial acceptace f maagemet sciece recmmedatis preseted i writte frm." subjects i the experimet were classified alg the field idepedece/ depedece dimesi f cgitive style thrugh the admii:;trati f a paper ad pecil test that was mdified frm Witki's rig:la1 Embedded Figures Test. 1 The subject (8) "was the asked t read a s:lmp1e busiess case which was adapted frm e used by Huysmas." The 1The wrk f Witki ad his assciates, i idetifyig ad develpig the field idepedece/depedece ccept, will be discuss1ad i a subsequet part f this secti.

49 31 S was asked t assume the rle f tp maagemet i the case situati. Next, S was preseted with e f tw versis (Rl r R2) f a "csultat's reprt". Rl ad R2 were distributed alterately amg S accrdig t rak the Witki test. After csiderig the reprt, S was asked t recrd a simple questiaire whether r t he wuld accept the csultat's recmmedatis. The csultat's reprts ctaied idetical aalyses f the case prblem ad the same recmmeded sluti, but differed i rgaizati ad presetati style. The majr differeces i the frmats f the tw reprts ca be summarized as fllws: Reprt 1 (aalytic) Reprt 2 (geeral) (1) Prblem Review (1) Recmmedati (2) Alteratives (2) Beefits (3) Chice Criteri (3) Alteratives (4) Evaluati (4) Evaluati (5) Recmmedati (5) Prblem Review (6) Beefits (6) Chice Criteri (7) Appedix (7) Appedix The appedix f Rl ctaied ly data tables, while the appedix f R2 als icluded all mathematical details (e.g., the regressi mdel) ivlved i the aalysis. I additi, R2 was rgaized with umerus subheadigs. The style f rgaizati f Rl was classified as aalytic ad, like Huysmas' explicit treatmet cditi, Rl ctaied frmulas i the mai bdy f the reprt. The style f R2 was classified as geeral. It is the style fte suggested by maagemet csultats i rder t achieve "mre effective implemetati" (fr example, see Neuschel [13]). Like Huysmas' implicit treatmet cditi, R2 ctaied frmulae r ther techical material i its mai bdy, leavig such "mathematical details" t the appedix (Ref 27, pp ). Dktr ad Hamilt's experimetal subjects were draw frm tw separate ppulatis: (1) graduate busiess studets frm a itrductry MBA curse at the Whart Schl, ad (2) practicig maagers attedig a "vlutary, e-day semiar implemetati prblems i the maagemet scieces." The availability f bth graduate busiess studets ad practicig maagers fr iclusi i the same experimet was a frtuitus ccurrece i regard t the results that were btaied. Althugh limited sample sizes did t allw detailed evaluati f the results, it was demstrated that maagerial acceptace behavir is iflueced by the style f presetati f maagemet sciece recmmedatis. Differet reprtig styles were bserved t have differet acceptace rates. Further, whe sample sizes were expaded thrugh use f studet subjects it became apparet that differet cgitive styles yielded differet acceptace rates fr the tw presetati styles uder study. The results als idicate that the use f studet surrgates- eve graduate busiess studet surrgates--i experimets ivlvig

50 32 maagerial decisi-makig behavir ca be misleadig" Whe a subsample f the studet grup was matched t the Witki scres f the maager grup, the studets shwed a sigificatly gr~~ater prpesity t accept a reprt idepedet f its style. This challeges the validity f geeralizatis frm the behavir f MBA utudet subjects t the behavir f maagers a t ucmm practice i maagemet research. This clearly suggests a eed t replieate previus experimets which have ivestigated maagerial behavir usig studet subjects. Such replicatis shuld, f curse, emply practicig maagers as subjects. Furthermre, cauti shuld be exercised i applyig priciples derived frm the geeralizatis f these earlier experimets util the results f the replicatis havl~ bee reprted ad aalysed (Ref 27, pp ). The results f these tw studies ted t idicate that cgitive style culd act as a pssible ifluece i the desig f data babes fr ifrmati systems. Fr example, the successful implemetati f data base systems might be retarded by a failure t iclude certai categril~s thse idividuals with particular cgitive styles might pl~efer. f data that experimetal effrt described i this reprt examies this type f pssibility i the desig f a data base fr a actual rgaizati. Maagers frm all levels withi the Texas Highway Departmet partic:lpated i a Delphi prcess t desig the Pavemet Feedback Data System (PFDS) data base, ad the Delphi grups i which these idividuals participa1:ed were structured relative t a dimesi f cgitive style. Theref:re, i this secti a review f the cgitive style literature will be udertake with the bjective f presetig, i a highly summarized frm sme f the may diverse dimesis that have characterized the develpmet f the (~cept. cgitive style dimesi that was selected fr use i the PFDS data base desig prject will be discussed i mre detail i Chapter 5, Measuremet Istrumets. Heiz Werer, i his frewrd t Witki et al (Ref 91), attempts t ffer a histrical perspective the develpmet f the cgitive style ccept. He states that The begiigs f these ivestigatis ca be traced back t the wrk f Gestalt psychlgists wh were i cstat search fr perceptual situatis that wuld demstrate the depedecy f perceptual prperties f parts f the field the (visual) field structure as a whle. I explrig such situatis ivlvig the perceptual prperty f the "upright" ad usig (i cllabrati with Dr. Asch) the famus mirrr set-up f Wertheimer, Witki s discvered that either the iterpretati i terms f uiversal visual Gestalt priciples, such The The

51 33 as that f part-whle relati, r the iterpretati i terms f pstural factrs (Gibs) suffices t accut fully fr the behaviral effects i the subjects. Mvig away frm a rthdx Gestalt-view as e "ecapsulated withi the rgaism" (Bruswik), Witki shwed that a rather satisfactry explaati culd ly be attaied thrugh a aalysis i terms f idividual differeces (Ref 91, p vii). The idividual differeces bserved were "that peple differ i the way they riet themselves i space." I additi it was fud "that the way i which each pers riets himself i space is a expressi f a mre geeral preferred mde f perceivig which, i tur, is liked t a brad ad varied array f persal characteristics ivlvig a great may areas f psychlgical fuctiig" (Ref 91, p 1). Thus, Witki ad his cwrkers, with their idetificati f the tw idividual mdes f percepti they labeled field-depedet ad field-idepedet (Ref 90), established the first cgitive style dimesi. Witki ad his cwrkers, i discussig the ccept f a geeral preferred mde f perceivig, state that The scpe f idividual csistecy i this respect is suggested by a brief csiderati f sme f the attributes f peple wh shw, i their rietati, what we call a "field-depedet" way f perceivig. This kid f rietati, bservable i ay f a series f tests devised fr ur early studies, may be illustrated by perfrmace i the rd-ad-frame test. The subject i this test sits i cmplete darkess, facig a lumius rd surruded by a lumius frame. Rd ad frame ca be idepedetly tilted, t e side r the ther; the subject sees them first i tilted psitis. The, while the frame remais tilted, he mves the rd (thrugh his directis t the experimeter) util it appears t him that it is vertical. Sme subjects tip the rd far twards the agle f tilt f the frame i rder t perceive it as upright, thus determiig its psiti maily i relati t the visual field that immediately surruds it. Here ad i ther perceptual situatis these subjects fid it difficult t vercme the ifluece f the surrudig field r t separate a item frm its ctext. It is because f this characteristic that their percepti has bee desigated field depedet. Other subjects, i ctrast, are able t brig the rd clse t the true upright, perceivig it idepedetly f the surrudig field ad determiig its lcati with referece t bdy psiti. I perceptual situatis geerally, such peple are able t distiguish a item frm its ctext. Their percepti is field idepedet. I the geeral ppulati perfrmaces reflectig the extet f peplef s field depedece r idepedece are raged i a ctiuum rather tha fallig it tw distict categries. Field-depedet peple take a rather lg time t lcate a familiar figure hidde i a cmplex desig. Because they are less likely t

52 34 attempt t structure ambiguus stimuli, as Rrschach ikblts, they usually experiece such stimuli as vague ad idefiit e. They fte fid difficulty with the blck-desig, picture-cmpleti, ad bjectassembly parts f stadard itelligece tests. Yet, they are differet frm mre field-idepedet peple ther prtis f itelligece tests which require ccetrated atteti; ad they may eve d better prtis ccered with vcabulary, ifrmati, ad cmprehesi. They are als t differet frm field-idepedet peple i the ability t lear ew material. I Ducker' s well-kw isight prblems they may t readily see alterative uses fr items servig a familiar fucti (Ref 91, pp 1-2). They als pit ut that peple wh demstrate "a predmiatly fieldidepedet way f perceivig preset a direct ctrast i 'ay f these attributesll(ref 91, p 3). I rder t vercme the difficulty ivlved i admiisterig the rdad-frame test t large umbers f subjects, Witki ad his assciates develped a paper ad pecil test t measure the field/depedeceidepedece ccept. figure withi a larger cmplex figure. "The subject's task is t fid a particular simple The figures which make up the test were selected frm thse develped by Gttschaldt (1926) fr his study f the rle f past experiece i percepti" (Ref 91, p 39). This test is called the Embedded Figures Test, ad a mdified versi f the rigial test was used by Dktr ad Hamilt i their study. Bth the rd-ad-frame test ad the embedded figures test have the cmm prperty that they require the subject t "keep a item separate frm a field r embeddig ctext. The item might be a stick i the rdad-frame test, r a gemetrical figure i the embedded figures test." I these situatis, fr the relatively field-depedet subjects, bject ad field ted t IIfuse,1I s that the separati called fr by the task cat easily be made. I this sese, the mre fielddepedet subjects' experiece ca be characterized as glbal. I ctrast, the perfrmace f a relatively field-idepedet pers, wh is able t keep bject ad field separate, ca be termed aalytical. It shuld f curse be ted agai that the terms "glbal" ad "aalytical" refer t extremes f a dimesi represeted by a ctiuus distributi f scres perceptual tests (Ref 67, p 172). "The glbal vs. aalytical style f experiecig exte,ds t a wide variety f itellectual tasks," ad "thus becmes a desiga.ti fr a cgitive style which expresses itself i bth perceptual ad itellectual fuctiig" (Ref 67, pp ),

53 35 Other ivestigatrs, subsequet t Witki, have idetified additial "cgitive ctrls," ad the glbal vs. aalytical mde f cgitive style ca be viewed as e f several dimesis f the cgitive style ccept. A cuple f these ther dimesis will be briefly reviewed i rder t preset the reader with a pprtuity t gai sme isight it the cmplexity ad lack f a uifyig thery that characterizes the preset rudimetary state f the cgitive style ccept. "The Levelig-Sharpeig priciple is curretly defied i terms f idividual csistecies i the degree t which ew experieces iteract r 'assimilate.' Subjects at the sharpeig ed f the ctiuum are thse wh shw a miimum f such mutual assimilati, subjects at the levelig ed shw relatively great assimilati" (Ref 67, p 195). "The Scaig priciple was rigially iferred primarily frm idividual csistecies i respse t size-estimati tests. The idividual csistecies bserved i simple size judgmets als seemed apparet, hwever, i ther situatis tappig the extesiveess with which perss sample bth exteral stimuli ad iteral memry schemata uder relatively 'free' cditis. Sme perss seem t sample extesively, whether r t this degree f samplig is ecessary fr effective perfrmace i the task at had. Such samplig may eve be a hadicap uder certai circumstaces i that it icreases decisi time. Others seem t atted primarily t 'dmiat' bjects i the field ad i ther ways t sca i a relatively restricted maer" (Ref 67, p 191). A recet research effrt has bee made by a research grup wrkig uder Prfessr James McKeey at the Harvard Busiess Schl t develp a uified mdel f cgitive style. Peter Kee, e f McKeey's assciates i the prject has cmmeted that theries f cgitive style all have the distictive weakess f lcality; i sme cases all they really shw is that subjects d well r badly the tests used t idetify the specific styles. Equally imprtat is the geeral tedecy fr mdels f style t pstulate a sigle dimesi with psitive-egative ples. The weakess f ay ui-dimesial mdel f huma thught prcesses is simply that it seems ulikely that it ca d justice t the cmplexity f huma thikig. T fit the immese rage f capacity ad respses that ay capable adult demstrates ver a variety f settigs it a sigle plarized dimesi is ievitably t limit the applicability f the mdel i questi (Ref 54, Chap 1, p 12).

54 36 The Harvard grup pstulates a mdel f cgitive style cmpsed f tw "relatively separable factrs, ifrmati-gatherig ad ifrmatievaluati." The mdel "defies the ifrmati-gatherig dimesi i terms f tw extremes f behavir, Receptive ad Preceptiv1;l." 'Preceptive' idividuals ted t brig t bear ccep'~s that they use t filter data; they fcus patters f ifrmati, lk fr deviatis frm r cfrmities with their expectatis. Their precepts act bth as cues fr ifrmati-gatherig ad as heu:ristics fr catalguig what they fid. By ctrast, the 'Receptive' thiker is much mre sesitive t the stimulus itself. He will fcus detail rather tha patter ad tries t derive the implicatis f the data frm direct examiati istead f frm its fittig his prt;lcepts. Each mde has advatages i specific situatis; equally, I:ach icludes risks f verlkig the ptetial meaig f data. The Preceptr t easily igres relevat detail while the Receptr may fail t shape detail it a cheret whle. I maagemet psitil3 the Receptr may be mst successful i tasks such as auditig ad the Preceptr i may marketig ad plaig rles. The secd dimesi f style, ifrmati-evaluati, refers t prcesses cmmly subsumed uder the term 'prblem-slvig'. Idividuals differ bth i hw they use data i reachig a decisi ad i the sequece f their aalysis. These differeces a~ mst pruced i relati t plaig. The mdel argues that 'SystE.matic' thikers ted t apprach a prblem by structurig it i terms f sme methd which if fllwed thrugh leads t a likely sluti, while 'Ituitive' idividuals usually avid cmmittig themselves i th:ls way; their apprach is much mre e f hypthesis-testig ad tjdal-ad-errr. They are much mre willig t jump frm e methd t ather, t discard ifrmati ad t be sesitive t cues that l:hey may t be able t idetify verbally. Here agai, each mde f 4avaluati has risks ad advatages. I tasks such as prducti ma.agemet a Systematic idividual ca develp a methd f prcedure - a prgram - that utilizes all his experiece. By ctrast the Ituitive is fte better able tha the Systematic t apprach ill-defied prblems where the vlume f data, the criteria fr acti r the ature f the prblem itself d t allw the use f ay predetermied pla (Ref 54, Chap 2, pp 1-2). Figure 5 presets a paradigm f the cgitive style mdel develped by the Harvard grup. The vertical axis reflects the ifrmal:i gatherig dimesi f the mdel, while the hriztal axjs presets the ifrmati evaluati dimesi. A particular cgitive style is def:led by the quadrat i which the idividual's style falls, e.g. Systematic-Recl~ptive Preceptive. r Ituitive Kee discusses the impact that cgitive style researc:h is likely t have the area f ifrmati systems desig. He states that "e lg-term

55 37 Ifrmati- gat herig PRECEPTIVE MODE Ifrmati - evaluati SYSTEMATIC MODE INTUITIVE MODE RECEPTIVE MODE Fig 5. A mdel f cgitive style (after Kee, Ref 54).

56 38 utput f the cgitive style research may well be a taxmy f ifrmati." He feels that the rgaizati's "MIS acts as a cgitive filter, selectig ad rgaizig data frm the evirmet. The cmputer system which geerates the ifrmati explicitly uses ccepts f what data is relevat, hw it shuld be frmatted, etc." If the fit betwee the user's cgitive style ad the ifrmati ctaied i ad utput frm a MIS is t take it csiderati, uiteded chages may take place i the user's prblem slvig behavir; lithe csequeces theref may be uaticipated." Kee demstrates this by pitig ut, i terms f the Harvard cgitive style mdel, hw idividuals with Systematic ad Ituitive styles apprach ad justify their slutis t prblems. The tw mdes f style result i very differet ways f justifyig slutis. The Systematic idividual ca validate his decisi prcess by recapturig his sequece f prblem-slvig. He ca. i fact lay ut the prgram he fllwed. He explicitly defied the prblem, chse a strategy ad prgressed methdically, aalysig ad evaluatig alteratives i relati t that strategy. The Ituitive, by ctrast, cat shw his sequece f thught. He ca fte ly backward iduct, pitig first t his sluti ad the shwig hw it is csistet with the features f the prblem. I sme cases he may t explicitly cmprehed but ly sese that sme data r assessmet has a particular relevace. I the last resrt, the Ituitive thiker ca ly justify the sluti t a cmplex elusive prblem by sayig 'trust me; my istict tells me it's right'. Successful Ituitives d build up a track recrd that gais them such trust. Ufrtuately they als may ted t justify a sluti, particularly t a Systematic superir, thrugh a pseudratializati. It is i such situatis that Ituitives get a reputati fr careless thikig, sice their explaati des t i fact match their prblem-slvig prcess; they are t facile i systematic evaluati ad the superir ca quickly pick hles i the reasig r pit t jumps i the argumet that may be valid but are t validated. The questi f hw e ca r shuld validate a sluti is very cmplex ideed. The issue t be raised here is that the differet mdes f style pse distict prblems f cmmuicati; ce agai, it must be stressed that either style is better tha the ther. The Systematic maager is t justified i dismissig the Ituitive as scatter-braied because he cat ratialize his decisi. O the ther had, the Ituitive cat take fr grated his 'bvius' sluti ught t be bvius t thers (Ref 54, Chap 3, pp 54-58). Summary Several experimets the Delphi Techique, which were cducted by the Rad Crprati wh are the rigiatrs f the methd, were reviewed.

57 39 These experimets prvide evidece that a large umber f peple are mre accurate ad reliable tha a few i makig judgmets as t bth factual ad pii type f material. The experimets als shw that the itrducti f iterati ad ctrlled feedback serves t icrease the accuracy f a grup respse, ad that a csesus reached thrugh a Delphi prcess is, i mst cases, mre accurate tha that btaied thrugh face-t-face iteracti. Opiis as t the efficacy f the Delphi prcess i prmtig grup acceptace were reprted, ad varius aspects f the Delphi Techique were examied. It was ccluded that, at least i thery, a Delphi type methdlgy is highly suited t the prblem f data base desig. A brief review f the cgitive style literature was cducted, ad tw experimets idicatig that cgitive style is likely t be a factr i the develpmet f ifrmati systems were examied. The semial wrk f Witki ad his assciates i the idetificati ad develpmet f the field/depedet-idepedet dimesi f cgitive style was ivestigated, ad tw ther cgitive ctrls were defied. The effrts f a grup, at the Harvard Busiess Schl, t develp a uified thery f cgitive style were discussed; ad their cgitive style mdel was preseted. Peter Kee's cmmets regardig the implicatis f this mdel fr the area f ifrmati system desig were reprted. The ext chapter will utilize the ifrmati that was cvered the Delphi prcess i the develpmet f a Delphi type methdlgy fr data base desig. Chapter 4 will the use ifrmati frm bth the Delphi ad cgitive style reviews t establish a experimetal desig fr ivestigatig the pssible ifluece f cgitive style i data base desig prcedures. Fially, Chapter 5 will agai refer t this review whe the selecti f a apprpriate cgitive style dimesi ad its assciated measuremet istrumet is beig discussed.

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59 CHAPTER 3. A DELPHI METHODOLOGY FOR DATA BASE DESIGN This chapter describes varius mdificatis t the Delphi Techique that have bee fud t ehace the techique's suitability as a methdlgy fr data base desig. The types f ifrmati that ca ad prbably shuld be btaied frm the ptetial users f a data base ifrmati system thrugh the use f the methdlgy are discussed; ad a type f techical ifrmati, pertiet t data base desig, that was idetified as mre difficult t btai frm the ptetial users f PFDS is examied. Methds f cductig a Delphi prcess fr data base desig are preseted, ad a geeralized cmputer prgram fr prcessig the Delphi ifrmati flws assciated with a data base desig effrt is described. A descripti f the actual applicati f the methdlgy t the determiati f what the ctets f the Pavemet Feedback Data System (PFDS) data base shuld be is prvided thrughut the chapter as a example t clarify the theretical ccepts that are ivlved. Types f Ifrmati The cetral theme uderlyig the prpsed methdlgy is that there are certai types f ifrmati ccerig what the ctets f a data base shuld be that ca be best prvided by the mst kwledgeable peple i the area, i.e. the ptetial users f the system. This is particularly true i the case f itegrated systems with cmm data bases. It is ureasable t expect a systems aalyst t pssess expertise i the systems area ad at the same time be kwledgeable eugh i all ther areas t be able t adequately prescribe fr the users f the system their ifrmati eeds. Eve if it were pssible t lcate such a versatile idividual r btai this ifrmati thrugh iterviews with the ptetial users, difficulty wuld still be ecutered i defiig a set f data items that were cgruet with the purpses f the rgaizati fr which 41

60 42 the system was t be desiged. N e idividual ca be expected t accurately make such a assessmet sice a rgaizati is by defiiti a cllecti f idividuals wrkig tgether. The ptetial users f the system actig as a grup shuld, therefre, theretically be the best surce f this ifrmati. Fr example, i the case f PFDS there are experts that deal maily with rigid pavemets, i.e. ccrete, ad ther experts that deal maily with flexible pavemets, i. e. asphalt. At the same time ther experts i fuctial areas such as maiteace are required t wrk with bth pavemet types. The bjective is t idetify a parsimius set f data items that ccurretly satisfies all f the users' ifrmati eeds ad which is als cducive t the accmplishmet f the rgaizati's purpse. Jerme Kater pstulates the existece f a pheme he calls the "gemetric rgaizatial sydrme" i his discussi f the prblems iheret i achievig the "cperati eeded t arrive at the pertiet data elemets" i a data base. He ccurs that "jit decisis are eeded t reach cmprmises related t the" data base ctet. HO'iiever, he sees this as beig a frmidable task, sice the umber f cmmuicati pathways betwee a expadig umber f peple icreases i apprximately a gemetric maer. He states that the "'gemetric rgaizatial sydrme' is prbably eve mre accetuated by the psychlgical ad plitical blcks that idividuals brig with them t the situati.. The sluti t these prblems rmally meas discussis, meetigs, ad evetual cmprmise if the implemetati time frame is t be met" (Ref 51, p 63). A methd, fr vercmig the "gemetrical rgaizatial sydrme" i a maer that allws the ptetial users t idetify the miimum set f data items ecessary t satisfy the requiremets f each user ad the rgaizati's purpse, is critically eeded. The use f a Delphi methdlgy appears t be e large step tward the accmplishmet f this bjective. The questi is what types f data base desig ifr:lilb.ti are the ptetial users capable f supplyig. I this secti the fcus will be describig a set f ifrmati items that ca be supplied ad evaluated by the ptetial users thrugh the use f the prpsed Delphi methdlgy. Al thugh these i te:ljl.s t date have ly bee btaied i e actual applicati, i.e. PFDS, they are still

61 43 felt t be geeralizable t a large umber f varied data base desig situatis. Hwever, sice the Delphi prcedures ca be easily mdified t accmmdate differet r additial items, the primary purpse f this secti is t demstrate a fuctial class f data base desig ifrmati items that ca be btaied frm the ptetial users thrugh the use f the methdlgy. Fr example, if further research idicates that ptetial users wh are experieced i data base systems are capable f supplyig techical ifrmati such as a key/-key desigati r hierarchical rderig f the data elemets, the these ifrmati items ca be easily added t the Delphi prcedures. I the PFDS experimet it was discvered that the participats, wh were all iexperieced with data bases, had difficulty i supplyig techical types f ifrmati. Therefre, ly -techical ifrmati items are used i the fllwig descripti which is iteded t demstrate the ptetial f the Delphi methd. The primary item f ifrmati, that the ptetial users are capable f supplyig, is a descripti f the elemetary data items that shuld be icluded i the data base. The ptetial users thus eed t prvide descriptrs r ames fr thse data items they feel are imprtat eugh t warrat iclusi i the data base. These descriptrs must ecessarily be specified i eugh detail t allw the admiistratr ad all ther participats i the prcess t uambiguusly idetify the data item beig prpsed. I additi, the descriptr may als ctai imprtat ifrmati regardig the frequecy with which the data item shuld be cllected tgether with ay dimesial ifrmati that might help t defie the data item. The frequecy prti f the descriptr ca be brke dw it bth time ad space cmpets. Fr example, if a participat is desirus f describig a data item fr the measuremet f deflecti alg a segmet f highway, he might prvide the descriptr - ANNUAL DEFLECTION EACH.5 MILE. Aual describes the participat's feeligs regardig the tempral frequecy with which the data item shuld be cllected, while the phrase, each.5 mile, reflects his piis regardig the desirable spatial frequecy fr cllecti. Dimesial ifrmati, such as lbs/i 2, sq yds, etc, ca als be supplied if it is ecessary t reslve pssible ambiguity. Hwever, it shuld be pited ut that verspecificati i the descriptrs leads t the rapid prliferati f similar data items that the grup must csider. Hece a diluti f effrt mre imprtat csideratis takes place. I

62 44 the applicati f the methd, it appears advisable that the participats be apprised f this trade-ff s they ca limit the descriptrs t sigificat phrases. I the PFDS data base desig effrt, the ifrmati regardig the frequecy f cllecti was csidered t be quite imprtat; ad the participats were ecuraged t take this it csiderati i their frmulati ad evaluati f data item descriptrs. Hwever, egieerig practice i the desig ad cstructi f highways was csidered t be stadardized t the pit where ay effrt spet i supplyig dimesial ifrmati wuld be uecessary. Therefre, the participats were specifically requested t t iclude dimesial type f ifrmati i their data item descriptrs. O the first rud f the Delphi prcess the participats are ecuraged t submit descriptrs fr all data items they feel might be eeded i the data base. The wrds, might be eeded, are used because durig the iitial submissi phase the emphasis is develpig all pssible data items. I this regard, the participats shuld be specifically istructed t supply descriptrs fr all data items they thik shuld be brught t the atteti f the Delphi grup. Eve thugh a participat may persally feel that a particular data item is relatively uimprtat it is still advatageus t have the grup cfirm r discfirm this pii. It shuld als be ted that the iitial submissi phase is cmpletely uihibited sice the participats wrk idividually durig this stage f the prcess; therefre, it is quite likely that multiple descriptrs with differet wrdig, will be received which describe essetially the same data item. Techiques fr hadlig this redudacy will be described i the ext secti f this chapter. The, i rder t prvide a meas fr grup evaluati as t the merit f the data items that have bee submitted, the participats are istructed t rate the items they submit i regard t imprtace. This imprtace ratig reflects the participat's subjective pii f hw imprtat he perceives the data item t be. Durig the successive iteratiills f the Delphi prcess, these imprtace ratigs are repeatedly fed back t<> the participats wh t ly review the ratigs their w descriptrs but als review the ratigs the descriptrs supplied by ther members f the grup. Thus, the imprtace ratigs are refied durig each rud f the pr<cess. Up the

63 45 cvergece f the prcess, the imprtace ratig reflects the grup's cllective judgmet as t the relative imprtace f the varius data items that were submitted. Sice the basic theme i applyig a Delphi methdlgy t the desig f a data base is the ivlvemet f a represetative spectrum f the ptetial users, a methd fr icrpratig the ecessarily wide rage f expertise brught t each data item is required. This ca be accmplished thrugh a self-appraisal techique where each participat is asked t rate his expertise each data item. This expertise ratig reflects the participat's subjective judgmet as t the degree f expertise he brigs t a particular data item, r i ther wrds the cfidece he has i his assigmet f the imprtace ratig t a data item. Ulike the imprtace ratig, the expertise ratig des t chage as a result f the iterative prcess. Oce a participat has assiged a expertise ratig t a particular data item he is ulikely t chage it uless a reappraisal reveals that the ratig was iitially i errr. As a example, i the PFDS desig effrt, there were participats wh had a great deal f experiece i the area f asphalt pavemets ad very little experiece i the area f ccrete pavemets. These idividuals wuld rate their expertise high the data items dealig with asphalt pavemets ad lw the data items dealig with ccrete pavemets. A similar situati existed i regard t fuctial psitis. The maiteace freme rated their expertise high maiteace related data items, but lw desig related items. A data base desig parameter f majr imprtace i terms f the success f a system, is the determiati f wh is gig t supply the data. As will be discussed shrtly i ather secti f this chapter, iitial presetatis were made t twety-five separate grups f the Texas Highway Departmet (THO) emplyees wh were t participate i the Delphi prject t desig the PFDS data base. Almst ivariably at the begiig f these presetatis, e r mre f the participats wuld iquire as t wh was gig t supply the data fr the system. These questis are a mir idicati f the widespread ccer, amgst the users f data base systems, regardig the determiati f wh will be respsible fr supplyig the data.

64 46 I the geeral case, this ccer culd stem frm a variety f causes. The requiremet f havig t supply a particular set f data items culd be viewed as the impsiti f a additial burde a already heavy wrk lad. Past experiece with havig t perfrm paperwrk, where the beefits were itagible, t immediately apparet, ad ly idirectly related t the accmplishmet f immediate wrk bjectives, may ted t lesse a emplyee's ethusiasm fr supplyig additial data. Kater cmmets that "i a highly decetralized rgaizati where divisis are autmus, the cetralizati f data i e cetral file ca represet a serius bstacle. The divisis are skeptical abut the ifrmati they submit; they wder hw it is gig t be used" (Ref 51, p 63). These ad may ther pssible prblems culd be reflected i the ptetial users ccer ver wh is t supply the data. I the PFDS presetatis, the reply, "Yu, the ptetial users ad suppliers, will determie wh the suppliers f the data itels will be," was always well received. Thus, it is therized that the actual data capture prcess will be facilitated by allwig the ptetial users ad suppliers t jitly participate i the determiati f wh will be respsible fr supplyig particular data items. It has bee previusly pited ut that grup csiderati i this type f situati is likely t lead t a mre accurate assessmet tha culd be made by a sigle idividual. Furthermre, i additi t btaiig a mre accurate determiati f the ptetial suppliers tha culd be develped by a systems aalyst, the act f participatig i the determiati prcess is therized t lesse the ptetial suppliers' resetmet tward the impsiti f a additial wrk lad. It shuld be csiderably easier fr the supplier t accept sueh a determiati frm a grup f his peers with whm he has participated tha it wuld be fr him t accept a similar determiati i the frm f a apparet fiat frm a systems aalyst actig i a staff capacity. Up util this pit i the Chapter a geeral class f data base desig ifrmati, which the ptetial users are capable f deteliig thrugh a Delphi type methdlgy, has bee demstrated by the use f examples frm the actual applicati f the techique t the desig f the PFDS data base. This geeral class f ifrmati ecmpasses thse types f ifrmati with which the ptetial user is i sme way familiar. Thifl familiarity might cme frm expertise i the area cvered by particular data items, r

65 47 it may cme frm areas f ccer the ptetial user might have. Hwever, it shuld be ted i the ext tw paragraphs, that durig the PFDS prject where the participats were iexperieced i data base ccepts, a attempt t exted the Delphi methdlgy it the area f ufamiliar techical questis met with failure. A shakedw f the Delphi prcess was ru a test grup f'24 subjects selected frm the THD ad the Ceter fr Highway Research (CFHR). The purpse f this test was t determie the feasibility f a Delphi methdlgy fr data base desig ad t validate the attitude scale as discussed i Chapter 5. Durig this test the participats were required t prvide ad evaluate the ifrmati discussed abve. I additi a attempt was made t have the participats rate the data items the techical questi f whether the item shuld be a key r -key item. I the presetati t the test grup, it was explaied that the key desigati a data item causes a iverted file t be cstructed fr that item; ad the iverted file ccept was the cvered i detail. Numerus questis were raised durig the presetati; ad subsequet aalysis f the participat's respses ad iterviews with them revealed that the ccept was t uderstd i eugh detail t allw itelliget decisis the key/-key questi. It was ccluded that, at least i the case f a ew applicati where the ptetial users are ufamiliar with data base ccepts, techical questis cat be cvered i the limited time rmally available fr a presetati the Delphi methd. Delphi Prcedures A set f prcedures was develped i the PFDS prject t prcess the ptetial users' respses i regard t the abve eumerated types f data base desig ifrmati. A discussi f these prcedures will help t clarify the methdlgy; hwever, befre prceedig it is ecessary t pit ut that these prcedures have t bee experimetally verified as beig a ptimal set. The purpse f the discussi, just as i the previus secti the types f ifrmati, is t demstrate a fuctial class f prcedures that ca be geeralized t a wide rage f data base desig prblems. The aim is t t specify a rigid techique i great detail, but rather t preset a methdlgy that ca be readily adapted by

66 48 ther data base desigers. Thus, the prcedures that were utilized i the PFDS experfmet are discussed alg with sme geeral suggestis i rder t illustrate e way i which the Delphi methdlgy might be applied t a geeral data base desig prblem. I geeral it is suggested that the grup f participats wh are t take part i the Delphi prcess be cmprised f idividuals frm all fuctial areas ad divisis withi the rgaizati. It is felt that widespread participati the part f the ptetial users will help t mre rapidly diffuse kwledge f the system ad prmte a greater degree f grup acceptace. Fr example, i the PFDS case 241 ptetial users cmprised f idividuals frm all 25 Districts, the Hust-Urba Office, Austi Headquarters Divisis, the CFHR, ad Texas Trasprtati Istitute (TTl) tk part i the data base desig effrt. The bjective i the selecti prcess was t balace the prprtial represetati accrdig t the umber f ptetial users i each District, Divisi, r research uit. I additi the represetati was als balaced accrdig t the prprtiate umber f ptetial users ivlved i each fuctial area such as desig, maiteace, ad research. It is estimated that i the PFDS case apprximately a fifth f the ptetial users tk part i the data base desig prject. After the participat idetificati phase has bee co:li1pleted a presetati shuld be made t the ptetial users wh have bee selected t participate i the Delphi prcess. Depedig the prir kwledge f the participats, the presetati shuld cver such subjects as a descripti f the prpsed system, its bjectives, basic data base ccepts, ad the prcedures fr the Delphi prcess f data base desig. At the ed f the presetati, a istructi bklet shuld be left with. each f the participats alg with the request that they sed their iitial submissi f data items i t the admiistratr withi a certai legth f time. As a example, a cpy f the istructi bklet used i the p:ms data base desig prject is icluded i Appedix A. Because f the glgraphically dispersed lcatis f the THD District ffices, 25 separat. presetatis were required i the PFDS case. The PFDS presetatis wer. als used fr the admiistrati f the measuremet istrumets required by the experimetal desig described i the ext chapter.

67 49 As the iitial submissis f data items are received frm the participats, it will be discvered that may f the data items are duplicates f items already submitted by ther participats. It is suggested that this situati be hadled by cmpilig a -redudat master list f data item descriptrs.,a uique item umber is assiged t each f the rigial items added t the master list. Thus, a item umber frm the master list ca be assiged t each data item descriptr a participat's iitial iput frm. After the iitial iput frms have bee received frm all participats, a cmpleted master list f -redudat items exists; ad each data item descriptr every participat's iitial iput frm ctais a item umber that matches a item umber the master list f data item descriptrs. It shuld be ted that the abslute elimiati f redudacy i the master list is t required, althugh it may be desirable. Fr example, i the PFDS prject the admiistratr was ufamiliar with pavemet termilgy; ad as a result, he was ly able t elimiate redudat items where the descriptrs ctaied similar wrdig. Redudat descriptrs that ctaied differet wrds describig essetially the same data item were t elimiated. It is pssible t admiister a Delphi prcess fr data base desig withut beig familiar with the techical questis ivlved. As the Delphi prcess prgresses the redudacies are discvered ad idetified by the participats wh have bee selected frm experts i the techical field uder csiderati. The ifrmati redudacies that is supplied by the participats ca be used t vercme the bimdal cvergece that is likely t take place whe tw separate descriptrs describig the same data item are preset. The prcedures fr hadlig this ccurrece are discussed at the ed f this secti after the ecessary backgrud the imprtace ad expertise ratigs have bee preseted. It is suggested that the participats be asked t idicate their imprtace ad expertise ratigs each data item by usig a 0.0 t 5.0 scale, with zer idicatig abslutely perceived imprtace r expertise with respect t the give item. Brief phrases describig the majr steps i the scales, i.e. 0.0, 1.0, 2.0, etc, shuld be prvided as rugh guidelies fr the participats. The guidelies fr the scales used i the PFDS prject ca be fud i the istructi bklet i Appedix A.

68 50 I the PFDS prject a average f the imprtace ratigs, weighted by the expertise ratigs, was determied fr each data item. That is Ai Ij~l I. E. = J J Ij~l E~ J i i where: idividual j's imprtace ratig fr item i. idividual j's self appraisa:l f his expertise i regard t item 1. = umber i grup. This average each data item was fed back t every member f the grup util cvergece was achieved. A estimate f the grup' II mvemet tward cvergece was btaied, after each iterati, frm the variace f the idividual imprtace ratigs abut the average imprtace ratig. That is I (Ai _ I~)2 j=l J = -l The variace t ly prvides a meas fr determiig whe cvergece has bee achieved, but it ca als be used t speed cvergece by fferig a meas fr decidig which items are imprtat eugh t be retured t the participats after each iterati. I rder t speed cvergece by elimiatig uimprtat data, the data items frm the grup are rak rdered Ai. Thse items that have a lw Ai ad a lw variace f Ii i j abut A, i.e. thse items that are uifrmly perceived t be uimprtat, are t retured t the participats after every participat has had a pprtuity t bserve each item at least ce. Althugh this feature is preset i the geeralized cmputer prgram that was used t prcess the ifrmati flws fr the PFDS data base desig prject, it was t used. All data items were retured t the PFDS participats utij~ cvergece all items was achieved. The prblem f bimdal cvergece, that is likely t ccur whe redudat data items are preset, ca be vercme by usig the ifrmati redudacies that is supplied by the participats. The participats shuld be istructed t give the redudat data items they least prefer a 0.0 imprtace ratig ad t give the item they prefer mst: i the

69 51 redudacy a regular imprtace ratig. After cvergece has bee achieved ad the redudacies have bee idetified, e.g. item 37 the same as item 103, the the imprtace ratigs the redudat items ca be cmbied; ad the items i a redudacy that are rated least i regard t imprtace ca be elimiated. If each e f the participats has fllwed the istructis explicitly ad has bee successful i idetifyig all redudacies, the the imprtace ratig f the remaiig item, i.e. the mst imprtatly rated item i a redudacy, ca be btaied by summig the imprtace ratigs f all items i the redudacy. Sice it is t likely that all participats will be able t crrectly idetify all redudacies, it is suggested that a pass thrugh the data item list f each participat be made. Durig this pass the imprtace ratigs f all items i a redudacy, ther tha the item i the redudacy with the highest expertise ratig, shuld be set t 0.0 ad all expertise ratigs i the redudacy shuld be set t the value f the highest expertise ratig befre perfrmig the summati prcess. This prcedure allws the reteti f the redudat data item that the grup mst prefers ad prvides fr the assigmet f the crrect imprtace ratig t it. A table which relates cde umbers t suppliers f data items shuld be established i rder t prvide a methd whereby the ptetial users ad suppliers ca determie wh will be respsible fr supplyig particular data items. The supplier cdes used i the PFDS data base desig prject are shw i Table 1 f the istructis which are icluded i Appedix A. The PFDS participats assiged e f the supplier cdes t each data item that they submitted, ad they als evaluated the supplier cdes all data items derived by the grup. The evaluati prcess tk place thrugh the mechaism f feedig back the mde, r mst frequetly appearig supplier cde, each item t all participats i the grup. The participats were thus able t idicate their agreemet r disagreemet with ay supplier fr a particular data item each iterati. Cvergece was fud t take place this value just as it did the imprtace ratig, althugh iitially there was widespread disagreemet the suppliers f certai data items i the PFDS prject.

70 52 Delphi Cmputer Prgram A geeralized cmputer prgram, fr prcessig the i:ermati flws ad implemetig the prcedures ivlved i a Delphi type data base desig effrt, was develped as a part f the PFDS prject. A cpy f this prgram, which autmates much f the ifrmati prcessig rlquired, is icluded i Appedix B. The prgram requires as iput the master list f data item descriptrs, that was previusly discussed, ad :lput frm each f the participats each f the data items. The prgrm~ utputs summary statistics fr the admiistratr ad letters t each f the grup members at the ed f each iterati. A descripti f the applicati f a prgram f this type t data base desig prblems will help t further clarify the methdlgy. Examples frm the PFDS prject are prvided i the discussi. As the iitial iput is received frm the participatb, each rigial data item descriptr is assiged a uique item umber; ad a file, which cmprises the master list f data item descriptrs, is devedped. The participats' data, which csists f a imprtace ratig" a expertise ratig, ad a wh supplies cde, ca the be etered i tel~s f a item umber. After all f the iitial iput frms have bee reeeived, the data frm the grup is prcessed. The weighted average f the imprtace ratig ad the mde f the wh supplies cde are calculated. The admiistratr has the pti f either receivig just a summary pritut, which raks the data items the average imprtace ratig ad presets the variace each item, r f als btaiig immediately the letters which cmmuicate the results t the members f the grup. The first pti is prvided i rder t allw the admiistratr t trucate data items, that are uifrmly perceived t be f lw imprtace, frm the list befre pritig the cmmuicatis fr the grup. The pritut that cmmuicates the results cmpiled frm the grup is mailed t each participat i the grup wh the idicates ay disagreemet he may have, regardig ay piece f ifrmati, directly em the pritut. A sample cpy f a Delphi coddiluicati is preseted i Figure 6. This hypthetical pritut has bee marked up by the participat, ad it is ready t be retured t the admiistratr as the participailt's iput t the secd iterati. Whe the participat first receives the pritut there

71 DELPHI COMMUNICATION PLEASE RETURN WITHIN FIVE D~YS RORERT J. ~U~PMY SUPERVISING CESIGN ENGINEER TEXAS MIr,H~AY OEPARrMENT 11 TH ANO SR AZOS AUSTIN, TEXAS INDIVIDUAL NUMeER 1 ITERATION NUMBER 1 IHPORT"NCE EXPERTISE WHO HEN RATING RATING SUPPLIES DATA ITEM DESCRIPTOR,.UMBER (0.0 TO 5.0) (0.3 TO 5.0) (CODE) (60 LETTERS AND EMSEDDED BLANKS) IS leo.3 10 NUMBER OF LANES LANE WIDTH 4.5 Z. 10 SUBGRADE SOIL TYPE 12 S. Z.7 5 ANNUAL AVEQAGE RAINFALL ANNUAL AVERABE TEMPERATURE 15 ~4.Z MATEAIAL TYPE FOR EA LAYER lit LAYER NUMBER 1'1 le5 Z. -H-a COST Of SUSGRADE PHEPAR_TIOH/LANE MILE JO La.ylr Thl<:.lte.s$ Fig 6. Sample Delphi cmmuicati. V1 w

72 54 are rmally blak spaces i the expertise clum. This i.dicates items that were submitted by ther members f the grup ad which have t yet bee reviewed by the participat t whm the pritut is addressed. The participat fills i the blak expertise spaces with his expertise ratig the particular items. I the example f Figure 6, items 9, 12, 14, ad 17 rigially ctaied blak expertise spaces. Althugh the expertise ratigs are the idividual's expertise ratigs, the imprta.ce ratigs ad the wh supplies cdes reflect a grup average. The partic.ipat may idicate his disagreemet with the grup ay piece f ifr~ti by crssig ut the questiable value ad writig his pii ut t the side. The participat is als allwed t eter ew data item descriptrs directly the pritut. The prcess is repeated util cvergece is: achieved. Cpies f the cverged prituts frm tw actual grups that participated i the PFDS prject are icluded i Appedix C. A cmputer prgram autmates the pritig f the letters ad allws all crrectis t be made directly the pritut. As e~lch iterati is prcessed, the participats' umdified iput fr the Succ~Edig iterati ca be utput t either magetic files r puched cards; ad the updatig prcess ca thus be carried ut either iteractively r maually. A prgram f this type allws a sigle admiistratr, with ly keypuch assistace, t prcess the iput frm a large umber f participats. Sice the umber f sigificat figures required i the imprtace ratig, expertise ratig, ad wh supplies cde is small, tt is pssible t pack the value f e f these variables fr several participats it a sigle cmputer wrd. Because f the ature f the prbj.em, the cde required fr the packig ad upackig peratis is relatj~vely efficiet. The prgram i Appedix B, which was used t prcess the ifrmati flws assciated with the PFDS prject, utilizes the packig priciple. PFDS Prject The PFDS data base desig effrt bega with 241 ptetial participats attedig the presetati. A ctrl grup f 27 idividuals, the purpse f which will be discussed i the ext chapter, was radly selected frm the larger grup. The ctrl grup atteded ly the firl;t half f the

73 55 presetati, which dealt with a descripti f the PFDS system ad its bjectives. The ctrl grup did t participate i the Delphi prcess t desig the data base. Out f the remaiig 214 ptetial participats 208 submitted their iitial iput frms fr the first iterati as requested i the presetati. These 208 participats were assiged t 20 Delphi grups f 10 idividuals each ad t e Delphi grup cmpsed f eight idividuals. The criteria used i the grup assigmet prcess will als be discussed i the ext chapter. At the start f the secd iterati fur participats had failed, fr varius reass, t retur their prituts; ad at the start f the third iterati tw participats were drpped frm the prcess because f retiremet ad a majr illess. By the ed f the third iterati all 21 grups had cverged ad the prcess was termiated. Because f the gegraphically dispersed lcatis f the participats, it was ecessary t use the mail bth ways i all cmmuicatis durig the prcess. It required apprximately fur weeks t tur arud each iterati, ad a ttal f apprximately three mths t ru the prcess t cvergece. The lw drp ut rate, f apprximately six percet ver the etire three mth perid, is viewed as beig a gd idicati f the degree f satisfacti that the participats fud i the 'prcess. This is especially sigificat i view f the fact that a third f the drps ccurred because f uavidable prblems such as a participat leavig the cutry, majr illesses, ad retiremet. It is als iterestig t te that, whe e ther retiree ad tw participats wh als uderwet surgery were give the pprtuity t drp, they isisted remaiig i the prcess. I additi, tw f the drputs wet ahead ad submitted their crrected prituts after the ext iterati was started, eve thugh they had bee istructed that their iput was lger required sice it was t late t icrprate their iput with the grups'. The PFDS master list f data descriptrs cvered 1310 data items at the time cvergece was achieved. Hwever, t all f these data descriptrs described uique data items sice the redudacies had t bee remved frm this list. The twety-e grups cverged separately data lists that raged i legth frm 89 t 293 data items. The reas fr the apparet discrepacy i the legth f the lists has t d with the way the

74 56 grups were structured relative t cgitive style. The sjlgificace f this legth differece will becme clearer i the fllwig chapters as the cgitive style experimet is described. There were idicatis, ther tha the key/-key prblem which ccurred i the test, that the PFDS participats had ay dhficulty whatsever i supplyig ad evaluatig the ifrmati that wah requested. The stadard idicatrs f a smthly fuctiig Delphi prcess, such as idividuals recsiderig their pii i light f the grup respse ad mvemet tward cvergece, were all preset i the PFDS prject. The prject prgressed just as expected except fr the speed wuh which the prituts were retured. Sice the participats were requested t retur the pritut withi five days f receipt, it had bee iitj~ally estimated that ly tw weeks wuld be ecessary t cmplete a iterti istead f the fur weeks actually required. Data was kept regardig the speed with which the prituts were retured, ad a iterestig relatiship betwee the participats' cgitive styles ad their speed f retur was ucvered. This relatiship is discussed i detail i Chapter 7. Ather bservati the speed f retur was that the early returers almst always retured the pritut early ad the late returers almst always retured the pritut late. N crrelati was fud betwee the speed f retur ad the attitude f the participats. I rder t prprtially distribute the represetat:l f the ptetial users i the PFDS prject accrdig t their fucti i the THO, fur basic categries were established: 1) Admiistrative Level Persel (14), 2) Other Egieers frm District Headquarters (31), 3) Egieers frm Residecies (30), ad 4) Maiteace Cstructi Supervisrs (25). The umbers i paretheses idicate the apprximate relati,re percetage f participati frm each f the fur fuctial categries. The experimetal desig which is described i the ext chapter required that the 21 grups be structured t a great extet alg ther dimesis; huever, where pssible a attempt was made t maitai a eve balace f idividuals frm each f the fur categries betwee the grups. Sice 21 separate Delphi grups were used i the PFDS prject, a methd f cmbiig the results frm the idividual grups was required. The assumpti was made that all grups pssessed apprximately the same level f cmpsite expertise ay particular data item. The assw~pti appears t

75 57 be valid, sice withi the cstraits f the experimetal desig a attempt was made t distribute idividuals with the same fucti evely thrughut the grups. The mea f the imprtace ratig fr each data item was calculated by usig all grups that cverged that particular item, e.g. if the cverged data lists f five ut f the 21 grups ctaied a particular data item, the the mea imprtace ratig f the five grups was calculated. The master list f data items was the rak rdered the mea imprtace ratig. The descriptrs fr the data items were utput i their rder f imprtace alg with the mea imprtace ratig, the umber f grups csiderig the item, ad the rage f the imprtace ratigs makig up the me~m. The results frm this utput were used t decide which data items shuld be icluded i the data base. If the mea imprtace ratig derived frm a large umber f grups was high ad the rage abut the mea small, the that particular data item was defiitely icluded i the data base. Similarly, if the mea imprtace ratig derived frm a large umber f grups was small ad the rage abut the mea was small, the the item was excluded frm the data base. The items that were t clearly defied by this set f criteria were set aside fr further csiderati ad aalysis by a systems aalyst. The PFDS prject was successful i its purpse f geeratig a large umber f data items ad brigig abut a csesus f pii amgst the ptetial users as t the relative imprtace f the varius items. It prvided data that culd have bee geerated by a systems aalyst ly thrugh massive iterviews ad umerus meetigs, if at all. Thus, a systems aalyst apprach t develpig the same amut ad quality f ifrmati regardig ptetial data items, wuld be a practically impssible task i a decetralized ad highly disbursed rgaizati such as the THD. The gegraphically disbursed ature f the 25 Districts i the THD leads t ather prblem that was vercme thrugh the applicati f the Delphi methdlgy t the desig f the PFDS data base. Because f their gegraphic separati, the Districts sustai widely varyig terrai, climactic, ad traffic cditis. The variace i these factrs ctributes t widely varyig data eeds amgst the Districts. Hwever, Delphi prvided a meas whereby the piis ad data eeds, f ptetial users frm all f the Districts, were itegrated it a sigle data base desig.

76 58 Summary It was fud i the applicati f a Delphi methdll~y t the desig f the PFDS data base that the ptetial users f the systlm are capable f supplyig ad evaluatig a certai class f ifrmati that is helpful i the desig f the data base. This class f ifrmati icludes descriptrs fr data items the ptetial users perceive as beig :lmprtat, a ratig f the degree f imprtace f each data item, a self appraisal f their expertise i regard t each data item, ad their piis as t wh shuld be respsible fr supplyig the data fr each item" Ather class f ifrmati, dealig with techical csideratis, was fud t be mre difficult t btai frm the ptetial users f PFDS wh wre iitially ufamiliar with data base ccepts. Prcedures fr admiisterig a Delphi methdlgy fr data base desig were discussed; ad the methds used t calculate the averclges, that were fed back t the participats durig the PFDS prject, were cvered i the discussi. A geeralized cmputer prgram t prcess the ifrmati flws assciated with the prcedures was described. Thrughut the chapter the emphasis was placed imp8,rtig the philsphy behid the Delphi methdlgy fr data base desi.g, rather tha prescribig a specific set f techiques i great detail. Althugh the specific prcedures appear t be geeralizable t a variety f data base desig siutuatis, it is felt that the greatest beefit is t be derived frm a uderstadig f the ccepts behid the methdlgy. Examples, take frm the applicati f the methdlgy t the desig f the PFDS data base, were used thrughut the chapter t illustrate the theretical ccepts. Fially, saliet aspects, f the applicati f the Delphi methdlgy i the PFDS prject, were preseted i rder t prvide the reader with a feelig fr the applicati f the methdlgy i a actual data base desig situati.

77 CHAPTER 4. RESEARCH DESIGN The Delphi methdlgy, that was reviewed i the precedig chapter, t ly prves t be a attractive methd fr data base desig; but it als ffers a research vehicle thrugh which the effects f sme persal characteristics f the ptetial users ca be ivestigated. Cgitive style, a persal characteristic f decisi makers, has bee idetified i the literature as havig pssible implicatis fr the desig f ifrmati systems. The impact f cgitive style the desig f data bases is ameable t aalysis thrugh the Delphi methdlgy; ad this chapter examies the cgitive style research scheme that was executed durig the Delphi prject t desig the PFDS data base. The hyptheses uderlyig the resea.rch effrt are preseted, ad the experimetal desig that was develped t test these hyptheses is described. Hyptheses The fact that aalytical idividuals have bee fud t be mre adept tha glbal idividuals at articulatig the reass ad specifyig the data behid their decisis leads t the speculati that the cgitive style variable is likely t be a factr i ay attempt t have the ptetial users f a data base participate i its desig. Oe majr ccer is the viability f the Delphi methd as a meas whereby the glbal idividual ca participate i the desig prcess withut beig verwhelmed r frustrated by the mre prfuse utput f the aalytical type. It is therized that the islati f participats i grups, where iteracti ly takes place amg idividuals with a particular type f cgitive style, might be a meas f vercmig this prblem. Ather imprtat ccer, i csiderig the pssible adpti f a Delphi methdlgy, pertais t the ptetial user's attitude tward the system befre ad after he has participated i the desig prcess. These ad ther ptetial ccers led t the frmulati f the fllwig fur hyptheses regardig the ifluece f cgitive style ad the effect 59

78 60 f user attitude i the Delphi methdlgy fr data base desig. Hypthesis 1: I the iitial rud f the Delphi prcess, the umber f elemetary data items submitted by participats will be sigificatly crrelated with their cgitive style. Hypthesis 2: Three distict sets f Delphi grups; the first cmpsed f mre aalytical participats, the secd cmpsed f mre glbal participats, ad the third cmpsed f participats fallig i betwee the glbal ad aalytical extremes; will cverge t data base desigs that are sigificatly differet. Hypthesis 3: A set f Delphi grups cmpsed f participats with least favrable attitude scres will cverge t a desig that ts sigificatly differet frm the desig btaied by grups with sidlilar cgitive style scres but higher attitude scres. I ther w{irds, a ufavrable attitude scre mderates the cgitive style effect. Hypthesis 4: The attitude scres f all grups will imprve as a result f participati i the Delphi prcess. These hyptheses were tested as a part f the Delphi prject t develp the data base desig fr PFDS. Hwever, the experimetal desig that was used t examie the validity f the hyptheses is presete~d befre udertakig, i subsequet chapters, the discussi f the results frm the statistical tests. Experimetal Desig I additi t the 24 test subjects wh were ivlved i the prelimiary shakedw f the methdlgy, 241 ptetial users actually participated i the PFDS data base desig prject; ad the sample used t test the fregig hyptheses was develped frm the 241 participats wh tc,k part i the PFDS prj ect. The iitial selecti f the participats was ac:cmplished by submittig a request t the heads f the Texas Highway Departmet (THD) Districts ad Divisis askig that they idetify a list f participats fr the prject. It was suggested that their selecti csist f spelcified umbers f

79 61 idividuals frm each f the fur fuctial areas utlied i the discussi f the PFDS prject i Chapter 3. The umbers suggested were based the prprti f idividuals rmally wrkig i each f the fur areas ad i each f the Districts r Divisis. A similar prcedure was fllwed i regard t the seve idividuals frm the Ceter fr Highway Research (CFHR) ad Texas Trasprtati Istitute (TTl). The iitial request was fr 230 participats; hwever, sme District heads requested that extra idividuals be allwed t participate, ad 241 peple eded up attedig the presetati t iitiate the Delphi prject. The fact that the District ad Divisi heads selected the idividuals t participate i the prcess, which resulted i the lack f a radm sample, was t felt t be a sigificat deterret t the research desig sice the sample was calibrated ad assiged accrdig t test scres. Each f the 241 idividuals that were selected frm the THO, CFHR, ad TTl, as was described i the precedig paragraph, atteded e f the 25 presetatis that were held i District ffices thrughut the state. I the first half f these presetatis the participats received istructi i the bjectives f the PFDS system ad elemetary data base ccepts. They were ifrmed that they had bee selected t take part i a prject t desig the data base fr the PFDS system. The scales fr the measuremet f the participats' cgitive styles ad their attitudes tward PFDS ad their participati i its develpmet were admiistered. Cmpleti f the tw tests eded the first half f the presetatis ad the participats were give a cffee break. Frm the selected sample f 241 ptetial PFDS users that was draw frm the THD, CFHR, ad TTl, as described abve, a radmly selected sample f 30 idividuals was desigated as the first ctrl grup. Durig the cffee break, which fllwed the first half f the presetatis, the idividuals desigated as part f the ctrl grup wuld be apprached ad asked t vluteer t act as ctrl subjects. They were istructed that they wuld have thig else t d with the prject util the rest f the grup had cmpleted the task f desigig the PFDS data base, ad they were ifrmed that they wuld the be asked t retake the attitude scale r Opii Survey, as it is titled. All f the subjects apprached agreed t this request, ad they did t atted the secd half f the presetati.

80 62 Durig the cffee break f the last presetati it was impssible t apprach the ctrl subjects, ad the secd half f the presetati bega with three f the desigated ctrl subjects preset. Sice the three subjects had received sme expsure t the Delphi ccept befre the errr was discvered, it was decided t allw them t act as regular participats ad t prceed with a first ctrl grup cmpsed f ly 27 subjects. The purpse f the first ctrl grup was t serve as a base pit fr ay attitude chage that might take place, the part f the participats, as a result f beig ivlved i the preess f desigig the PFDS data base. The secd half f the presetati ccetrated prvidig the participats with a backgrud Delphi ad the prcedure fr applyig the techique t the desig f the PFDS data base. A descripti f the techique was preseted, ad the rigi f the methd was discussed. Examples f the applicati f Delphi i bth gvermet ad private busiess were prvided, ad sme f the experimets cducted by Rad were brught t the grup's atteti. Examples f the types f data items that the grup was expected t prvide fr the PFDS data base WEre cvered, ad the iitial iput frms the participats were t use i submittig their data items were displayed. A simulated ru thrugh the prcess was described by usig the example frm the sample Delphi cmmuicati that was preseted i Figure 6. After the mechaics f the prcess were cvered, the participats were give the istructi bklet, that appears i Appedix A, alg with several blak iitial iput frms. They were requested t cmplete these frms ad retur them t the admiistratr withi fi,re days, if pssible. This request was a attempt t assure everye, frm all f the 25 separate presetatis, apprximately the same amut f ttme each iterati f the prject. A fial precauti was take at the ed f the presetati. As is stadard i the Delphi Techique the participats were cautied agaist talkig with aye abut the prject util its cmpleti was auced by the admiistratr. The purpse f this measure was t ly t maitai the itegrity f the Delphi prcess by assurig that iteractic. tk place ly thrugh the Delphi medium, but it was als used t mattai the itegri~ f the experimetal desig. Sice the experimetal grups were t be

81 63 segregated accrdig t their cgitive style, it was imperative that uiteded iteracti take place acrss the grups. The cauti t the grups regardig the itegrity f the Delphi prcess thus served t accmplish bth f these bjectives withut havig t reveal the experimetal aspect f the prject. The umerical scres, btaied frm gradig the cgitive style ad attitude scales that were admiistered durig the first half f the presetatis, were used i assigig the participats t Delphi grups. Details ccerig the selecti f the cgitive style scale ad the cstructi f the attitude scale are preseted i the ext chapter. Befre applyig the umerical scres btaied frm the scales, a secd ctrl grup f 40 subjects was radmly selected frm the first 200 active Delphi participats wh submitted their iitial iput frms. The last eight active participats t submit iitial iput frms were assiged t a grup that did t take part i the cgitive style research effrt. The assigmet f the remaiig 160 active subjects was made t fur distict sets f majr Delphi grupigs which were amed; Aalytical, Glbal, Mixed, ad Attitude. This assigmet was made withut the subjects' kwledge ad befre Delphi feedback was give t the participats t begi the secd rud f the desig. The 40 subjects with the least favrable attitude scres were assiged t the attitude grup. The remaiig 120 subjects were assiged by rak rderig their cgitive style scres. The 40 subjects with the highest cgitive style scres were assiged t the Aalytical grup; the 40 subjects with the lwest cgitive style scres were assiged t the Glbal grup; ad the 40 subjects i the middle f the cgitive style distributi were assiged t the Mixed grup. The sample assigmet prcedure is reiterated ad graphically illustrated i Figure 7. Begiig at the upper left ad mvig t the lwer right, 27 f the 241 subjects (8's), wh atteded the presetatis, were radmly selected fr the first ctrl grup as was previusly described. After receipt f 200 iitial iput frms, 40 f the subjects were radmly assiged t the secd ctrl grup. The remaiig 160 subjects were raked accrdig t their attitude scres, ad the 40 subjects with the lwest attitude scres were assiged t the attitude grup. The remaiig 120 f the first 200 subjects t respd were the raked accrdig t their cgitive

82 S', Atteded Preset at is 27 S', 40 S's 160 SiS Raked Attitude (U f a vr a b Ie) 40 S's First Ctrl Secd Ctrl Attitude 120 S', Raked Citive Style (Aalytical), 40 S, Aalytical Delphi 40 S's Mixed 40 S' Glbal ( Favrable) (Glbal) 14 Sal 8 st, 6 S', Extra Grup IDrpped Fig 7. Sample assigmet.

83 65 style scres. The 40 subjects i the aalytical third f the cgitive style ctiuum were assiged t the Aalytical grup. The 40 subjects i the middle third f the ctiuum were assiged t the Mixed grup. ad the 40 subjects i the glbal third f the ctiuum were assiged t the Glbal grup. Out f the remaiig 14 subjects. eight submitted their iitial iput frms befre the first iterati was begu. ad tgether they were assiged t a extra Delphi grup. The six subjects wh did t respd i time were drpped frm the prcess. The purpse f the secd Ctrl grup was t prvide a bservati as t hw participats wuld respd whe lumped tgether i Delphi grups withut regard t cgitive style. ad the Attitude grup ffered a meas f determiig hw ptetial users with lw attitudes tward a system are likely t perfrm i a Delphi prcess t desig the system's data base. The first Ctrl grup ad the six subjects wh were drpped did t participate i the Delphi prcess, ad althugh the extra grup did participate i the Delphi prcess. they were t a part f the cgitive style experimet. The five primary grups--g10bal. Mixed, Aalytical. Attitude» ad the secd Ctrl--were brke dw it smaller Delphi grups i rder t btai a sufficiet umber f replicatis t supprt the statistical aalysis f the hyptheses. I attemptig t determie the umber f idividuals t assig t each Delphi grup a trade-ff was ecutered. The larger the umber f replicatis the mre apparet wuld be ay differeces frm the cgitive style effect. Hwever. the larger the umber f Delphi grups the smaller wuld be the grup size; ad a lss i accuracy ad reliability wuld be suffered as a result. I rder t reslve this trade-ff. referece was made t Figures 3 ad 4 i Chapter 2. I a Delphi grup f seve participats, bth the reliability ad the accuracy is idicated by the figures t be fairly high; ad seve is a cmm umber f participats fud i the Rad grups. It was decided that seve participats per grup wuld be sufficiet fr the purpses f the PFDS prject ad the cgitive style experimet. Therefre. t vercme the effect f further drp uts ad t be sure that the grups wuld ctai at least seve participats at the time f cvergece. it was felt that iitially 10 subjects per Delphi grup wuld be required. Thus, fur grups

84 66 f 10 subjects each were frmed it actual Delphi grups ~'ithi each f the five primary grups. This prcedure resulted i the fc'rmati f 20 Delphi grups cmpsed f 10 subjects each t participate i the cgitive style experimet. Assigmet f idividuals t the fur Delphi grups withi each f the five primary grups was perfrmed i such a maer as t make the fur grups as hmgeeus as pssible. This was de i a attempt t vercme the effect f the small umber f replicatis per treatmet. All available ifrmati regardig the subjects, such as attitude scres, cgitive style scres, ad departmetal psitis, were used i the hmgeizig prcess. Idividuals were assiged t the fur grups s the mea ad rage f the attitude ad cgitive style scres were apprc1ximately the same fr each f the grups. The grup assigmets were als balaced i relati t the subjects' psitis bth fuctially ad lcatially where pssible. It was hped that by balacig the fur DE~lphi grups withi each primary grup the effect f variace due t variables ther tha attitude r cgitive style wuld be miimized. Cmputer prcessig was required i rder t accmmdate the large vlume f ifrmati trasfer assciated with the PFDS data base desig prject, ad a umberig scheme fr the Delphi grups was E~stablished t facilitate this prcessig. Each idividual participatig i the experimet was assiged a umber which expressed his psiti i regard t each f the five primary grups ad als i regard t his Delphi grup. These umbers fr the 200 subjects raged frm 10 thrugh 209. The last digit the right expressed the idividuals's psiti i his Delphi grup, while the digit r digits t the left f the right mst digit ide~tified which e f the 20 Delphi grups the subject was assiged t. Grups 1 thrugh 4 were Glbal grups, 5 thrugh 8 were Mixed grups, 9 thrugh 12 were Aalytical grups, 13 thrugh 16 were Attitude grups, ad 17 thrugh 20 were Ctrl grups. Thus, idividual umber 10 idetified the first idividual i the first Glbal grup; ad idividual umber 209 idetified the last idividual i the last Ctrl grup. The eight parttcipats i the extra grup were assiged idividual umbers 210 thrugh 2J.7, ad the 27 subjects i the first ctrl grup were assiged idividwll umbers 501 thrugh 527. The idividual umbers fr the varius primary grups appear the bxes idicatig these grups i Figure 7.

85 67 The Delphi prcess was idepedetly ru t cvergece i three iteratis fr each f the 21 grups. Durig the prcess six participats drpped ut f five Delphi grups fr varius reass that were discussed i Chapter 3. Therefre, the lwest umber f participats i aye grup at cvergece was eight. This figure is mre tha was required, sice ly seve participats were deemed ecessary, i each Delphi grup at cvergece, t maitai the desired accuracy ad reliability. Cmmuicati with the participats was cducted by mail after the iitial presetati except fr a limited umber f telephe calls placed either by a participat t pse a questi r by the admiistratr t check it late replys. After cvergece f the data base desig had bee achieved i each f the 21 grups, the attitude scale was readmiistered by mail t all f the participats wh were still active. Oe f the primary bjectives, i the develpmet f the experimetal desig fr the cgitive style phase f the experimet, was the miimizati f the pssibility f itrducig experimeter bias it the prcess. This bjective was t adherred t r eve csidered desirable i the Delphi evaluati phase f the prject. I the Delphi evaluati phase the admiistratr made every effrt t cduct the Delphi prject i the best pssible maer. The bjective was t determie if a Delphi methdlgy fr data base desig culd b~ applied successfully i a actual applicati. Eve thugh the pssibility des exist that ather admiistratr culd cceivably preset the methd i such a maer as t cause its failure, this fact is t csidered t be relevat. Hwever, the validity f the cgitive style results is iextricably liked t the experimetal desig; therefre, bth the strgest ad the weakest aspects f the desig, i regard t the itrducti f experimeter bias, are discussed. The miimizati f the reactive effect t the measuremet istrumets is felt t be the strgest aspect f the experimetal desig. All, but e f the 200 participats, were cmpletely uaware f the cgitive style experimet that was beig cducted as a part f the PFDS prject. The fact that a experimetal Delphi type methdlgy was beig used i the desig f the PFDS data base was the extet f the participats' kwledge ccerig the ature f the prject. The admiistrati f the cgitive style scale was explaied durig the presetati as beig a methd fr

86 68 determiig the amut f detail the participats wuld pre~fer i the utput frm the system. The fact that the cgitive style scre ~ru1d als be used as a basis fr assigmet t Delphi grups was t merltied, ad there was idicati durig the experimet that ay f the participats guessed this purpse. Likewise, the attitude scale was admiistered uder the title Opii Survey; ad its purpse was explaied as a methd fr btaiig the participats' piis regardig the system befre ad after they were familiar with the data ctets f the data base. It was explaied that these piis wuld be used i evaluatig the decisi f whether r t t prceed with implemetati f the system. Sice the cgitive style prti f the experimet was t apparet t the participats, it is ulikely that the cmm experimetal effect, f the subjects tryig t please the experimeter, was preset i regard t the cg:l.tive style phase f the experimet. I additi, further mitigati f pselible reactive effects was felt t take place as a result f the Delphi me~thdlgy. The Delphi requiremet f havig t agree as a grup is believed t suppress sme f the reactive tedecies that might be fud whe dealig with idividuals. It is difficult t imagie a ucscius cspiracy the part f the grup t adpt, fr example, a Glbal respse set.ad t play ut the Glbal rle as a grup. The weakest aspect f the experimetal desig derived frm the ecessity f the admiistratr havig t grade the cgitive style scales ad als havig t develp the master list f data items. It D~y be theretically pssible, althugh practically impssible i a highly cmplex situati such as PFDS, that the admiistratr culd have ucsciusly memrized the 200 cgitive style scres ad the ucsciusly tried t structure the 1300 data item master list i rder t prduce a cgil:ive style effect i the experimet. It was aticipated that a few cmplaits might be registered by partic.ipats because f the slight chages i the wrdig f data items that was ecessary i rder t elimiate redudacy. Thus, evidece that the abve metied experimeter effect did t take place i the PFDS experimet ca be fud i the fact that.ly e participat registered a mild cmplait that the retured utput did t exactly match his iitial iput.

87 69 Summary Fur majr hyptheses ccerig the ifluece f cgitive style ad the attitude f ptetial users i a Delphi methdlgy fr data base desig were frmulated, ad a experimetal desig which was develped t test these hyptheses was preseted. The prcedures, fr sample selecti ad fr utilizati f the scres btaied frm attitude ad cgitive style scales i assigig participats t Delphi grups, were discussed. It was pited ut that the criteria used fr the selecti f the cgitive style scale ad the cstructi f the attitude scale wuld be cvered i the ext chapter. A umberig system which was devised t facilitate the cmputer prcessig f the participats' replys was als described. Fially sme stregths ad weakesses f the experimetal desig were preseted.

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89 CHAPTER S. MEASUREMENT INSTRUMENTS Methds fr umerically scrig the behaviral dimesis f cgitive style ad attitude are ecessary i rder t implemet the experimetal desig utlied i Chapter 4. Therefre, this chapter describes the istrumets that were selected ad develped t umerically assess the cgitive style ad attitude characteristics f the idividual participats. The first secti f the chapter discusses a cmmly used istrumet, fr measurig cgitive style, that was selected fr use i the PFDS data base desig prject. The secd secti deals with the steps that were fllwed i rder t mdify a recetly validated attitude scale t make it applicable t the PFDS effrt i the THD. Hidde Figures Test The wrk f McKeey, Kee, ad thers, which was summarized i Chapter 2, Review f the Literature, has bee directed tward the develpmet f a cmprehesive mdel f cgitive style. This authr views the McKeey, et al wrk as hldig frth the pssibility f evetually culmiatig i a sud mdel fr use i cgitive style research. Hwever, the fact that the mdel utilizes twelve writte tests requirig e-ad-a-half hurs cupled with the fact that the mdel is still i the prelimiary stages f develpmet mitigated ay ethusiasm fr its adpti i the PFDS prject. The mre traditial views f cgitive style, which have received wide recgiti i the literature, were adherred t i the search fr a suitable cgitive style istrwet. As was als discussed i Chapter 2, the ccept f cgitive style is characterized by may diverse behaviral dimesis such as percepti, adaptati, itellect, ad persality. I ur preset rudimetary stage f uderstadig there has bee a tedecy t ccetrate particular aspects f cgitive style; ad e all ecmpassig measure has t bee develped, althugh tests have bee perfected which address a specific 71

90 72 dimesi f the ccept. Therefre, "fr research purpses cgitive style has bee peratially defied i terms f the testig situatis; that is, istrumets, used t measure it" (Ref 32, p 8). Several criteria were emplyed i the prcess f seleetig a cgitive style dimesi ad its assciated istrumet fr use i the PFDS prject. First, it was csidered essetial that the istrumet be (:sistet with the ature f the task that the participats were beig asked t perfrm, i.e. articulate data items used i their decisi makig ejtperiece. Secdly, it was highly preferable that the istrumet be a stadardized test develped by experieced testig specialists. Fially, it was csidered desirable that the test have a prir histry f be:lg emplyed i similar lies f research. Frtuately it was pssible t lcate a istrumet that meets all f the abve criteria. The Hidde Figures Test (HFT), develped by the Educatial Testig Service f Pricet, New Jersey, i 1963, is a adapted vcrsi f the rigial writte test which was used by Witki t determi4 a subject's ability t vercme a embeddig ctest. Educatial Tes1:ig Service's desigati adapted vel'si idicates that the test is "paj'»auez with the rigial test" (Ref 37, p 4), i.e. withi measuremet errolr measures the same variable. The wrk f Witki ad his assciates, 1:he field depedece-field idepedece ccept, represets the first ad mst extesive bdy f research i the cgitive style field. ~rhe ccept has bee examied i depth ad widely reprted i the literatu:re. I this wrk Witki has shw that the ability "t keep a item separatl frm a field r embeddig ctext" is related t the field depedece-field idepedece r glbal-aalytical ccept (Ref 67, p 172). I additi it has bee shw "that ability t break up a existig structure ad the abuity t structure a ustructured situati ted t g tgether" (Ref 67, p 175). I ther wrds, the aalytical subject is better able t impse structure a field. Furthermre, the ability t articulate experiece has bee shw t be liked with aalytical ability (Ref 67, p 176). Sice the participats i the study were beig asked t pull data items frm a ust:ructured ctext, it was ccluded that the HFT adequately meets the first c't'iteri. Educatial Testig Service's extesive experiece i test develpmet ad admiistrati uequivcally satisfied the secd criteri; therefre,

91 73 atteti was directed tward determiig if similar research had bee cducted with either the HFT r the parallel Embedded Figures Test used by Witki. It was fud that Dktr ad Hamilt, i their study f the relatiship betwee maagemet reprtig styles ad cgitive style, emplyed the rigial Embedded Figures Test i their experimet (Ref 27, p 885). Thus the third criteri was als satisfied, ad the HFT was selected fr use i the PFDS data base desig prject. The HFT is a multiple chice test which requires the subject t decide which e f five simple gemetrical figures ca be fud i a mre cmplex patter. The maual fr admiisterig the HFT idicates that it tests "the ability t keep e r mre defiite cfiguratis i mid s as t make idetificati i spite f perceptual distractis" (Ref 37, p 9). The test csists f tw parts each with 16 items, ad the subject is allwed 10 miutes t cmplete each part. The level f difficulty f the test is high ad a wide variace i scres has bee fud. The subject's cgitive style scre is the umber f right aswers crrected fr guessig by the fllwig frmula: W S = R -- 4 where S is the crrected scre, R is the umber f right aswers, ad W is the umber f wrg aswers. The higher the subject scres the test the mre aalytical is his cgitive style. A cpy f the directis fr the HFT, which iclude tw sample items, ca be fud i Appedix D. Attitude Scale A search f the literature failed t reveal the previus existece f a scale develped expressly fr the purpse f measurig attitudes tward data base systems. I additi, whe csiderati was give t the pssibility f develpig a scale specifically fr the purpse f the PFDS research effrt, it was ccluded that difficulty wuld be ecutered because f the limited ppulati t which the scale wuld be applied. It was cceivable that almst the etire ppulati, ccered with PFDS withi the THD, culd have bee ctamiated by a attempt t develp a

92 74 suitable attitude scale. Frtuately a geeralized scale used t measure attitudes tward aye f a geeral class f OR/MS mdel referets was lcated. The attitude scale recetly validated by Schultz ad Slevi fr OR/MS mdel implemetati was selected ad mdified fr use i the experimet. This istrumet was desiged s that it wuld "be applicable t a variety f ppulatis ad a variety f ivatis" (Ref 78, p 18). The istrumet was pilt tested 136 MBA studets at the Uiversity f Pittsburgh ad the field tested i a large heavy maufacturig cmpay i the Pittsburgh area. The attitudes f 98 ptetial users f a MIS ivati, that was scheduled t be implemeted i the cmpay, were measul:-ed with the attitude scale. These attitude scres were fud t be sigif:lcatly crrelated with a expressed iteti t use the MIS ivati whe it became peratial. The Schultz ad Slevi istrumet is based the Likert summated ratigs techique. I this methd f attitude measuremet th,~ subjects are required t select aye f five categries: strgly d:lsagree, disagree, ucertai, agree, r strgly agree t express their respse t each statemet i a set f statemets. Althugh the rigial Schultz ad Slevi scale csists primarily f favrable statemets, it is traditial that the set f Likert statemets be cmpsed f tw apprximately,~qual classes f statemets differetiated it favrable ad ufavrable categries sice "attitudes are leared predispsitis t respd t a psyehlgical bject i a favrable r ufavrable way" (Ref 35, p 257). These categries are weighted such that the mst favrable attitude will always have the highest psitive value. I the favrable statemets, the strgly agree respse is assiged a weight f fur, the agree respse a weight f three, the udecided respse a weight f tw, the disagree respse a weight f e, ad the strgly disagree respse a weight f zer. I the ufavrable statemets, the scrig system is reversed, with the strgly disagree respse beig assiged the weight f fur ad the strgly agree respse the zer weight. The subject's ttal attitude ratig is the btaied by summatig his scres frm each f the idividual statemet i the set. The Schultz ad Slevi istrumet rigially csisted f 67 items; hwever, a factr aalysis f the data btaied i bth the pilt ad field

93 75 tests idicated that ly 57 f the 67 Likert items laded seve factrs, which were defied as: 1. Maager's jb perfrmace 2. Iterpersal relatis 3. Chages resultig frm mdel 4. Gal achievemet ad cgruece 5. Supprt fr the mdel 6. Cliet/researcher iterface 7. Imprtace ad urgecy f results. Schultz ad Slevi feel that these factrs "are csistet with previus empirical fidigs ad meet a priri expectatis." I additi, they feel that these factrs "prvide useful guide-lies fr future research by allw- ig the ivestigatr t fcus a small umber f behaviral dimesis" (Ref 78, p 19). I rder t decide which f the 57 statemets, that laded the seve behaviral dimesis, t iclude i the PFOS attitude scale, it was first ecessary t gai a clear ccepti f the attitude variable tward which the PFOS scale was t be directed. Shaw ad Wright state that As the attitudial referet is cceived t be gal facilitatig, it will be evaluated psitively; it is evaluated egatively t the extet that it is cceived as ihibitig r iterferig with gal attaimet. This affective, evaluative reacti will be mre itese as the gal is mre imprtat t the cceiver (Ref 80, p 6). This prperty f attitudes was selected as the first criteri fr evaluatig the suitability f the Schultz ad Slevi items fr iclusi i the PFOS attitude scale. It was assumed that the mre PFDS is see t facilitate the gals f the user the mre favrably will he ted t view PFDS. I ther wrds, statemets were selected that appeared t have a direct relatiship t the subject's persal r rgaizatial gals. A secd criteri that was used i the selecti f statemets was the factr ladigs assciated with each f the 57 items. Frm thse items that clearly reflected the gal relatiship, the items with the highest ladigs were selected. This tw level selecti prcess resulted i twety-tw f the Schultz ad Slevi statemets beig icluded i the PFDS attitude scale. Te f these statemets came frm the Jb Perfrmace dimesi,

94 76 fur frm the Gals dimesi, tw frm the Supprt dimesi, tw frm the Cliet/Researcher dimesi, ad fur frm the Urgecy dimesi. The tw statemets frm the Cliet/Researcher dimesi, alg with three ther statemets develped by this authr, were icluded i Part II f the PFDS scale which measures the subject's attitude tward his participati i the PFDS data base desig. The remaiig twety statemets fr<:)m the ther dimesis were used t make up Part I f the scale which deals with the subject's attitude tward PFDS itself. Several f the Schultz ad Slevi statemets were altered slightly t better reflect the statemets' pertiece t PFDS. I additi, sice it was desirus f adherig t the traditial Likert framewrk f apprximately e-half favrably wrded ad e-half ufavrably 'wrded statemets, te f the Schultz ad Slevi items had t be mdified t take a egative ctati. This was a precautiary measure t avid th'e pssibility f the subjects develpig a respse set t the questiair,e. After the statemets were suitably rewrded, their rder f appeara,c:e i the PFDS scale was determied by a radm assigmet prcedure. The tw part, twetyfive item scale resultig frm this prcess served as the startig pit fr further validati. Althugh it was strgly felt that the discrimiate s,electi f statemets with the highest factr ladigs frm a previusly wl1idated scale wuld i itself result i a adequately valid ad reliable scale fr PFDS use, further validati prcedures were emplyed as a check. Prir t utilizig the scale the test grup f 24 subjects, a cr.. de apprximati f validity ad reliability was btaied by havig a grup f te subjects adpt a attitude set tward PFDS befre cmpletig the qulestiaire. Five f the subjects were istructed t adpt a favrable attit\lde set ad the ther five a ufavrable set. The mea scre frm the five favrable subjects was high (85.8) with a lw stadard deviati (6.9), ad the mea scre frm the five ufavrable subjects was lw (13.6) with a lw stadard deviati (7.3). Albeit crude, these fidigs idicate th.t the scale pssesses a high degree f cstruct validity. As a by prduct f this prelimiary testig it was discvered that e f the items was ambiguusly wrded, thereby allwig a crrecti t be made befre adliisterig the scale t the test grup f 24 subjects.

95 77 I additi t the cstruct validity a split-half reliability was als ru the data btaied frm the te prelimiary subjects. I the split-half methd, the ttal umber f statemets is divided it tw parts ad each part is treated as a separate scale. The reliability measure is the crrelati betwee the scres the separate parts. Sice a radm assigmet f statemets had bee previusly made fr the PFDS scale, it was decided that the eve umber statemets wuld cstitute e part ad the dd umber statemets the ther part. Detig the crrelati cefficiet r reliability measure by p, it was fud that p =.98 fr the crrelati betwee the dd ad eve halves. This crrelati cefficiet was the reliability fr a scale ly e-half as lg as the scale actually used i the prject; therefre, a methd fr estimatig the reliability f the larger scale was required (Ref 84, p 87). The Spearma-Brw Prphecy frmula idicates the icrease i reliability that ca be expected as a fucti f the legth f the scale. The revised reliability (pi) is give fr a scale that is times lger tha the rigial scale by the frmula pi _ p (-l)p I the case f the split-half methd = 2; ad substituti f p =.98, which was calculated fr the half scale, yielded a revised reliability estimate pi =.99. This very favrable result, althugh quite crude, prmpted the decisi t prceed with the use f the attitude scale fr the test grup. A mre refied itepal csistecy reliability estimate was btaied frm the results f admiisterig the scale t the test grup f 24 subjects by the widely used Crbach a methd (Ref 84, p 89). reliability estimate a is calculated frm the frmula: L 0 2 a = ~[l_i=ll -l 2 x I this methd the where is the umber f items i the scale, L OI is the sum f the diagal elemets f the cvariace matrix, ad i is the variace f the ttal

96 78 scale. This methd ffers a mre pwerful reliability est:lmate sice it "examies the cvariace amg all f the items simultaeusly rather tha i a particular ad arbitrary split" (Ref 84, p 87). Aalysis f the results f the attitude scres f the test grup yielded all a f.91. Sice the Crbach a iteral csistecy reliability estimate was als fud t be very favrable, it was ccluded that the attitude scale was adequate fr use i the PFDS prject. A cpy f the attitude scale is icluded i Appedix D uder the title PFDS OPINION SURVEY. Swmary The selecti f a apprpriate cgitive style dime:3i ad its assciated measuremet istrumet(s) was limited t thse egitive style ccepts that have bee reprted i the literature ad are widely recgized ad accepted by wrkers i the field. The first ad mst I:xtesive bdy f research i the cgitive style field is that related t Witki's field depedece-field idepedece ccept. Sice this ccept pstulates a predispsiti t behave i certai ways i situatis clsely related t the task that the participats were beig asked t perfrm i desigig the PFDS data base, the Hidde Figures Test (HFT), which is us,:d i measurig this ccept, was selected fr umerically assessig the p,uticipats' cgitive style. A attitude scale that had bee previusly validated fr use i OR/MS mdel implemetati was mdified ad tested fr use i the PFDS prject. Durig the testig phase the mdified scale was fud t have a very high iteral csistecy reliability; therefre, this mdified attitude scale was adpted fr use i the PFDS data base desig prject. The tw istrumets ffer a meas fr umerically scrig the experimetal dimesis f cgitive style ad attitude. Thus the scres btaied frm admiisterig the HFT ad the attitude scale were used i statistically testig the hyptheses put frth i Chapter 4, Research De:dg. The results frm the statistical tests f these hyptheses are discussed i the remaiig chapters.

97 CHAPTER 6. COGNITIVE STYLE AND THE ARTICULATION OF DATA ITEMS The first hypthesis i Chapter 4 pstulates a relatiship betwee a ptetial user's cgitive style ad his ability t idepedetly develp data items that he perceives as beig imprtat i a data base. I a Delphi methdlgy, the participat is iitially faced with the task f extractig ifrmati frm his experiece, that deals with his past decisis r decisis that he aticipates i the future; ad he is asked t supply this ifrmati i a specific frm. The first secti f this chapter examies the ature f this task i terms f the cgitive style ccept ad sets ut the assumptis that led t the frmulati f Hypthesis 1. The, the secd secti f the chapter presets the results frm the test f Hypthesis 1 that were btaied i the cgitive style experimet which was cducted as a part f the prject t desig the PFDS data base. The sigificace f the results are discussed i terms f the implicatis they hld fr the PFDS cgitive style research effrt. Nature f the Task I supplyig data items fr ptetial iclusi i a data base, the Delphi participat is called up t idetify types f ifrmati that he feels might be imprtat i prblem situatis likely t cfrt him i the future. As was discussed i Chapter 1, if the variables ad iterrelatiships amgst the variables i a prblem situati are well defied, the eed fr a data base system, ther tha fr archival purpses, is small. It is i ambiguus ad cmplex prblem situatis that the eed fr a data base system is greatest. Thus, almst by defiiti, the participat i a Delphi type data base desig prject is faced with a cmplex ambiguus evirmet. Therefre, i accmplishig his task f supplyig data items, the participat is required t differetiate ad articulate the relevat elemets f this cmplex stimulus. He is required 79

98 80 t vercme the embeddig ctext f the whle prblem ad t idetify the parts f the prblem that are pertiet t its sluti. lie must the restructure the elemets he has idetified i rder t preet them i the specified frm. May f the varius aspects f the task, that the participat is beig required t perfrm whe he is asked t supply ptetial data items, have bee fud t be related t the field-depedet/idepedet r glbalaalytical ccept. I the review f the literature that 'ias cducted i Chapter 2, it was shw that Witki ad his assciates have fud the glbal idividual t be less adept at vercmig a dmia1: rgaizati i his attempts t idetify relevat discrete items withi a f~mplex field. I additi, the glbal idividual has als bee fud t be less adept at structurig ambiguus stimuli. Fr example, glbal peple require a relatively lger time t lcate a familiar figure hidde :I a cmplex desig; ad i the Rrschach ikblt test the glbal pers is usually uable t impse rgaizati the stimulus material, wh:lch he usually perceives as vague ad idefiite. The Delphi participat is i essece beig asked t idetify the ccepts uderlyig the particular prblem fr which the data base is beig desiged ad t articulate these ccepts i the f f relevat data items. A recet study by Davis ad Klausmeier (Ref 23) ivestigated the relatiship betwee a subject's perfrmace a stadard ccept idetificati task ad his cgitive style as measured by the Hidde Figures Test. "A idividual's cgitive style was fud t ifluece his ccept idetificati perfrmace. Idividuals idetified as aalytical the Hidde Figures Test experieced little difficulty ill idetifyig ccepts while subjects (lw aalytic) wh experieced difficulty i lcatig the simple figures i the Hidde Figures Test experieced csiderable difficulty i ccept idetificati. Idividuals fallig i the middle f the Hidde Figures Test distributi perfrmed at a itermediate level f perfrmace the ccept idetificati task" (Ref 23, p 427). Peter Kee, whse wrk was als reviewed i Chapter 2, has attempted t relate cgitive style t idividual decisi makig. He cautis that certai types f idividuals, whm he characterizes as Ituitive, are uable t recstruct the steps they fllw i arrivig at prble'lil slutis because these steps are ukw t them. Therefre, Kee feels that the

99 81 ituitive type simply cat articulate the types f data they use i their decisi makig activities. The csideratis, eumerated abve, led t the assumpti that the cgitive style f participats is likely t be a ifluece the umber f data items they submit fr the iitial rud f the Delphi prcess. It was assumed that the glbal type idividual wuld be less likely t submit a large umber f data items tha the aalytical type idividual. These csideratis ad assumptis were used i the frmulati f the hypthesis that, i the iitial rud f the Delphi prcess, the umber f elemetary data items submitted will be sigificatly crrelated with the participats' cgitive style. Crrelati Fud i PFDS Experimet I the PFDS cgitive style experimet the subjects' cgitive styles alg the glbal-aalytical dimesi were assessed with the Hidde Figures Test (HFT). The scres the HFT raged frm -3 t 26 fr the 241 participats i the prject. A cut was als take f the umber f data items each f the 208 active participats submitted fr the first rud f the Delphi prcess t desig the PFDS data base. The umber f items iitially submitted raged frm 4 t 179 fr the 208 active participats. The pertiet data, the 241 participats i the PFDS prject, is icluded i Appedix E. The first clum f this data is the idividual umbers that were described i the discussi f the sample assigmet prcedures i Chapter 4. The secd clum ctais the HFT scre fr each idividual, ad the third clum is the umber f data items submitted by each f the participats fr the first rud. The ther clums ctai the prir ad pst Delphi attitude scres ad the rakigs f the participats i regard t their HFT ad pre-attitude scres. The pre-attitude ad pst-attitude scres will be referred t i Chapter 8 whe the effect f participati the ptetial users' attitudes is reprted. The places where blaks r zers ccur i the data, ther tha i the HFT scres, idicate that the participat drpped ut f the prcess; ad a rugh idicati f whe the idividual drpped ca be btaied frm the csiderati f which scres are missig.

100 82 A crrelati cefficiet was cmputed betwee the HFT data ctaied i the secd clum ad items submitted data ctaied i the third clum. The crrelati cefficiet (r) btaied betwee the HFT scres ad the data items submitted was.230; ad this crrelati was fud t be sigificatly greater tha zer at the ~.0005 level. Therefre, the cefficiet f determiati (r2) equals.053, which idicates that apprximately five ad e-half percet f the factrs ctributig t the participats' perfrmaces the HFT als ctribute t their perfrmaces i submittig data items. I the PFDS experimet the cefficiet f determiatiq is t ly small, but as i all crrelatial aalysis there is fi'~ evidece t supprt a iferece that cgitive style accuts fr evel~ this small cmm factr that was fud betwee the participats' perfrmaces the HFT ad their submittal f data items. Fr example, lle rival hypthesis, althugh it is t viewed by this writer as beig hi:~hly plausible, might be that itelligece accuts fr bth the HFT ad d.~ta item submittal perfrmaces. Eve thugh attempt was made t,:trl fr IQ i the experimet, the credibility f this rival hypthesi:g is i dubt because all participats i the prject held respsible pl)sitis ad were selected with regard fr their ability. Hwever, the fact remais, it is cceivable that sme plausible rival hypthesis may accullt fr the cmm factr that was fud. The sigificat psitive crrelati.) betwee HFT scres ad data items submitted ca ly, at best, prvide a pssible idicati that cgitive style accuts fr bth perfrmaces. The sigificace f pssibly accutig fr ly five ad e-half percet f the variace i terms f cgitive style may, at first glace, appear t be mir; hwever, whe viewed frm the perspect:lve f what culd be expected, the fidigs take a added sigificace f:r the PFDS cgitive style research effrt. There are may prbable su:rces, ther tha cgitive style, effectig the variace i the participat:i' submittal f data items. The amut f time each participat has avail.~ble fr the prject ad the participat's familiarity with the subject f the prject prbably have a great deal t d with the umber f items he submits. Fr example, i the PFDS prject, researchers wh were itimatlly familiar with the PFDS ccept appeared t be mre likely t submit a large umber