Contents. Interactive Mapping as a Decision Support Tool. Map use: From communication to visualization. The role of maps in GIS

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1 Contents Interactive Mapping as a Decision Support Tool Claus Rinner Assistant Professor Department of Geography University of Toronto otru gis workshop rinner(a)geog.utoronto.ca 1 The role of maps in GIS From communication to visualization Interactive maps to explore smokingrelated variables Spatial decision support Interactive maps to evaluate tobacco control options otru gis workshop rinner(a)geog.utoronto.ca 2 The role of maps in GIS Cartography: art, technique, and science Paper map functions Piece of art Data storage (parcel maps) Decision support tool (military) GIS map functions View of geographical database Part of the software's user interface Map use: From communication to visualization Source: MacEachren and Kraak homepage/sad/cageo/cgvis/ mk/mkintro.htm otru gis workshop rinner(a)geog.utoronto.ca 3 otru gis workshop rinner(a)geog.utoronto.ca 4 Map use: From communication to visualization Communication Present known facts to the public in static maps e.g. OTRU publishes maps of spatial distribution of key smoking indicators on its Web page Visualization Display unknown data in a research setting using interactive maps e.g. OTRU researchers explore smoking-related variables in GIS Interactive maps to explore smoking-related variables Demo application Public health unit boundaries from StatCan (generalized by U of T Cartography Office) 26 variables from Canadian Community Health Survey 2001 (processed by OTRU) CommonGIS software (Fraunhofer research institute) otru gis workshop rinner(a)geog.utoronto.ca 5 otru gis workshop rinner(a)geog.utoronto.ca 6

2 Interactive maps to explore smoking-related variables CommonGIS demo, part 1 Classified choropleth map of <% daily smokers> Unclassed choropleth map of <% intention to reduce smoking> Cross-classification (bi-variate choropleth map) of <% daily smokers> and <% intention to reduce smoking> Classified choropleth map otru gis workshop rinner(a)geog.utoronto.ca 7 otru gis workshop rinner(a)geog.utoronto.ca 8 Unclassed choropleth map <% intention to reduce smoking> Bi-variate choropleth map, <% intent. reduce smoking> otru gis workshop rinner(a)geog.utoronto.ca 9 otru gis workshop rinner(a)geog.utoronto.ca 10 Summary, part 1 Interactive maps to Display spatial distribution, patterns Classify regions visually Compare regions to a reference value/region Dynamically linked maps and graphs for Multi-variate analysis through object selection and highlighting Explore data Generate hypotheses otru gis workshop rinner(a)geog.utoronto.ca 11 Spatial decision support Decision problem A situation calling for a change of action Different possible (feasible?) solutions ("decision alternatives") Tobacco research & control as a spatial decision problem Health variables referring to geographic regions Evaluate current smoking status of regions Develop need indicators for campaigning activity otru gis workshop rinner(a)geog.utoronto.ca 12

3 Spatial decision support systems (SDSS) SDSS suggests a plausible decision, cannot make a decision Decision-making may use/need researcher's intuition, group negotiation, Use of GIS for the quantifiable aspects of spatial decision problems System components: database, model base, user interface, report generator Rational decision often involves multiple decision criteria Process of criterion standardization, weighting, aggregation Calculation of final evaluation scores according to an aggregation operator ("decision rule") otru gis workshop rinner(a)geog.utoronto.ca 13 otru gis workshop rinner(a)geog.utoronto.ca 14 Source: Heywood et al (GIS textbook) otru gis workshop rinner(a)geog.utoronto.ca 15 otru gis workshop rinner(a)geog.utoronto.ca 16 otru gis workshop rinner(a)geog.utoronto.ca 17 otru gis workshop rinner(a)geog.utoronto.ca 18

4 Implementation in GIS Raster GIS: Pixel-by-pixel overlay of criterion maps resulting in an overall suitability map e.g. using ArcView ModelBuilder Vector GIS: Arithmetic calculations in feature attribute table e.g. using CommonGIS Sample decision rules Simple Additive Weighting: s i = Σw j c' ij Ordered Weighted Averaging Analytical Hierarchy Processing Related concepts Suitability/vulnerability indicators Statistical indices otru gis workshop rinner(a)geog.utoronto.ca 19 otru gis workshop rinner(a)geog.utoronto.ca 20 Assumptions Known, limited set of decision alternatives (health regions, facility locations) Numeric, uncorrelated, commensurate criteria Quantifiable decision-maker preferences (criterion standardization, weighting) Interactive maps to evaluate tobacco control options Demo application as above Selected variables used as decision criteria Benefit vs. cost criteria % daily smokers: cost criterion % intention to reduce smoking: benefit criterion % male population:??? otru gis workshop rinner(a)geog.utoronto.ca 21 otru gis workshop rinner(a)geog.utoronto.ca 22 Interactive maps to evaluate tobacco control options CommonGIS demo, part 2 Simple additive weighting of "core" variables Simple additive weighting of "smoking cessation" scenario Simple additive weighting of "second-hand smoke" scenario Core analysis <% occasional smokers> <% other tobacco> <# cigarettes/day (daily smokers)> <# cigarettes/day (occasional smokers)> <# years smoking (daily smokers)> otru gis workshop rinner(a)geog.utoronto.ca 23 otru gis workshop rinner(a)geog.utoronto.ca 24

5 Smoking cessation analysis <% occasional smokers> <% other tobacco> <% nicotine replacement therapy use> <% attempting to quit within last 12 months> <% intending to reduce smoking> Second-hand smoke analysis <% occasional smokers> <% other tobacco> <% exposed to second-hand smoke> <% living in homes with smoking restrictions> otru gis workshop rinner(a)geog.utoronto.ca 25 otru gis workshop rinner(a)geog.utoronto.ca 26 Comparison of results Table of scores and rankings according to previous analyses Summary, part 2 Interactive maps in conjunction with multicriteria decision analysis for Instant display of spatial patterns of aggregated indicators (scores) Exploration of modified aggregation settings (criterion weights) Comparison of need indicators for different scenarios Evaluation of geographical units otru gis workshop rinner(a)geog.utoronto.ca 27 otru gis workshop rinner(a)geog.utoronto.ca 28 Specialized evaluation methods Ordered Weighted Averaging (OWA) Definition of decision strategies in terms of decision risk and criterion tradeoff Analytical Hierarchy Process (AHP) Definition of a criterion hierarchy Pairwise comparison of criterion importance otru gis workshop rinner(a)geog.utoronto.ca 29 Conclusions Interactive and dynamically linked maps to explore data ("visual analysis") Evaluate status quo of public health units Plan programs and campaigns Interactive maps in conjunction with multicriteria evaluation to explore decision scenarios Measure need for improvement Control effectiveness of programs otru gis workshop rinner(a)geog.utoronto.ca 30

6 Conclusions Other GIS functions of interest not dealt with in this talk, include Map design for reporting and publishing Web publishing Geographic data management Spatial analysis References Online demo application, CommonGIS software, I Heywood, S Cornelius, S Carver (2002) An Introduction to Geographical Information Systems. Prentice Hall. 2 nd edition. J Malczewski (1999) GIS and Multicriteria Decision Analysis. John Wiley & Sons. Computers & Geosciences 23(4) (1997) Special issue on Exploratory Cartographic Visualization otru gis workshop rinner(a)geog.utoronto.ca 31 otru gis workshop rinner(a)geog.utoronto.ca 32