Development of the Web System of Small Area Population Projections

Transcription

1 1 Development of the Web System of Small Area Population Projections TAKASHI INOUE AOYAMA GAKUIN UNIVERSITY(JAPAN) VISITING SCHOLAR AT UNIVERSITY OF WASHINGTON (UNTIL AUGUST 31) ESRI USER CONFERENCE 2017 JULY 12, 2017

2 CONTENTS 2 1. Aim of this Presentation 2. How to Perform Small Area Population Projections 3. Our New Methods of Small Area Population Projections 4. Outline of the Original Web Systems 5. Demonstration of the Original Web Systems

3 AIM OF THIS PRESENTATION 3 The aim of this presentation is to introduce two original websites the author developed on ArcGIS Online and to show their efficacy. Both the websites are about long-term small area population projections, and one is for the whole Japan; the other is for the state of Washington.

4 HOW DO WE PERFORM SMALL AREA POPULATION PROJECTIONS? Basically we perform population projections using the latest two census population data on the assumption that the changing trends between the censuses are constant, but But? Small area population projections are much more difficult than general ones. 4

5 HOW TO PERFORM SMALL AREA POPULATION PROJECTIONS Why are small area population projections so difficult? Because small area demographics are very unstable, and especially in the case of long-term projections, a small estimation error often generates an extremely huge population due to its amplification. 5

6 OUR NEW METHODS OF SMALL AREA POPULATION PROJECTIONS To solve such problems on small area population projections, the author proposed two new methods. One of them is ESAD method, a method of estimating small area demographics from those of its adjacent areas. How are small area demographics estimated using ESAD method? 6

7 OUR NEW METHODS OF SMALL AREA POPULATION PROJECTIONS It s one of spatial filtering and its image is as follows: 7

8 OUR NEW METHODS OF SMALL AREA POPULATION PROJECTIONS For the details of this method, please see the author s paper included in the newest book of Springer s Applied Demography Series, which was edited by Swanson, D. A. (2017). 8

9 OUR NEW METHODS OF SMALL AREA POPULATION PROJECTIONS The other is TSS method, a two step smoothing method for small area demographics. Why do we need a further method? Because for example, to smooth demographics of a census block group, smoothing after smoothing those of a county using those of the state is much better than simple smoothing as shown in the next slide. 9

10 OUR NEW METHODS OF SMALL AREA POPULATION PROJECTIONS 10 The Standard Census Geographic Hierarchy and the Step Path of Smoothing no smoothing one-step (tract) one-step (county) one-step (state) two-step (tract) two-step (county) the State counties 0 1 census tracks 0 1 block groups =small areas census blocks 0 1:first step 1 2:second step

11 OUR NEW METHODS OF SMALL AREA POPULATION PROJECTIONS 11 What should we do if we want to know the details of TSS method? Sorry, the paper on that method is now being submitted. Please wait for some time.

12 OUTLINE OF THE ORIGINAL WEB SYSTEMS 12 The Web System of Small Area Population Projections for the Whole Japan: a trial ver. was released on Jun 2015 a regular ver.1.0 was released on July 2016 ver. 2.0 is scheduled to be released on July 2017 The Web System of Small Area Population Projections for the state of Washington: a trial ver. is scheduled to be released on July 2017

13 OUTLINE OF THE ORIGINAL WEB SYSTEMS 13 All users of both the systems can freely download the forecasted populations by sex and 5-year age group on a per small area basis. Particularly the system for Japan opened such long-term small area forecasted populations of the whole Japan to the public for the first time.

14 OUTLINE OF THE ORIGINAL WEB SYSTEMS 14 characteristics of small area unit of small areas number of small areas system for Japan cho-cho and aza about 217 thousand system for WA census block group 4,783 average size (square kilometer) average population in 2010 about 1.74 about about 590 about 1,406

15 ACKNOWLEDGEMENTS 15 The author is grateful to the geographers and demographers at the Office of Financial Management, the state of Washington, including Yi Zhao, Mike Mohrman, and Thomas Kimper, for providing small area data of the state and for advising on data handling. The author also appreciates the assistance of Atsushi Kajimoto (Esri Japan Corporation) for constructing original websites on ArcGIS Online.

16 REFERENCES 16 Inoue, T. (2014) A new method of estimating small area demographics using population potential. Working Paper Series, Institute of Economic Research, Aoyama Gakuin University, , Inoue, T. (2017) A new method for estimating small area demographics and its application to long-term population projection , Swanson, D. A. ed., The Frontiers of Applied Demography, Applied Demography Series 9, Springer International Publishing Switzerland.

17 17 Let s Start Demonstrating WELCOME TO THE WORLD OF THE WEB SYSTEM OF SMALL AREA POPULATION PROJECTIONS FOR THE WHOLE JAPAN AND THE STATE OF WASHINGTON!

18 Thank you for your attention 18