What is the population of Afghanistan?

1. What is the population of Afghanistan? Kim Bradford Smith; Nicola Wardrop and Frances Harper. DFID

2. What is the population of Afghanistan?

3. What is the population of Afghanistan? Pick a number!

4. What is the population of Afghanistan? Possibly somewhere between 27m (official estimates) and upwards of 32m (UN estimates) [as of 2015]

5. Some challenges…(in 2015) • Limited infrastructure – eg physical & statistical infrastructure • Capacity (CSO donors) • Extremely low staff knowledge, ability and exposure to official statistics (including Head) • Disputes over province and district boundaries, and ownership and use of maps • Soviet legacy of statistical secrecy • Security • Politics!

6. Exams for the enumerators in Samangan Data editing of Kabul questionnaires

7. The census methodology • A census has not been politically agreed • But there is a statistical compromise … • Socio-Demographic and Economic Survey (SDES) • Province by province (from 2011 to 2018) • Listing of all households • Enumeration of 50% of households • Publication province by province • But what about the national picture? • Not including ethnicity questions • Not publishing numbers!

8. Mapping and listing Samangan Kabul

9. The Kabul province results • Kabul city comprises ¾ of the province population. • Population density is 7907 people per km2. • Average HH size is 6.9. • Literacy rates vary (higher than other provinces); • 55% for ages 15 and above • 71% for 15-24 year olds • 64% of the population were not engaged in economic activities 12 months before the survey. • One in every 5 deaths in the past 2 years were children below the age of 5. • 3 in 4 HHs have access to improved water • 2 in 5 HHs have access to improved sanitation • LPG is the main source of energy for cooking (82%) for HH

10. So…what is the population of Afghanistan?

11. Population enumeration data from Afghanistan SDES

12. Population estimation approach • Enumerate population in defined areas • Link with spatially continuous covariates which are correlated with population density • Use statistical modelling to predict population in un-surveyed areas

13. 1. Enumerate population

14. Population enumeration data from Afghanistan SDES + micro-census

15. 2. Link with covariates Compound points (license from Alcis Holdings Limited) Compound density Vegetation index Slope Nighttime lights

16. 2. Link with covariates • Summarise covariates at the same spatial level as enumeration • Min, mean, max values • Area of settlement • Number of buildings Within polygons

17. 3. Predict population • Compared regression model types and potential covariates • Training subset used (80%) • Optimised predictive R2 • Minimised error as % of observed population count

18. 3. Predict population • Linear regression model selected • Spatially structured random effect was included, with a CAR prior • This is then used to predict population in un-enumerated areas • Also provides uncertainty quantification • Model validation using independent data subset

19. 3. Predict population

20. So…what is the population of Afghanistan?