DESIGN OF A SUBNATIONAL POPULATION PROJECTION MODEL FOR ETHNIC GROUPS AND FOR DEALING WITH UNCERTAINTY IN INTERNAL MIGRATION Philip Rees BSPS Day Meeting on Population Projection, 29 February 2008 London School of Economics and Political Science, Houghton Street, London ESRC Research Award RES , What happens when international migrants settle? Ethnic group population trends and projections for UK local areas School of Geography FACULTY OF ENVIRONMENT

Aims – To project the ethnic populations of local areas (authorities) in the UK over the next 50 years (project) – To explain the model design being developed (presentation) Outline – State space of model – Accounting framework – Model structure – Internal migration model – Ethnic mortality estimation – Ethnic fertility estimation – New Migrant Databank – Feedback School of Geography FACULTY OF ENVIRONMENT

School of Geography FACULTY OF ENVIRONMENT Source: Dunnell, K. (2007) The changing demographic picture of the UK: National Statistician’s annual article on the population. Population Trends 130, STATE SPACE Zones (434) (O origins, D destinations) England 354 LAs Wales 22 UAs Scotland 32 CAs Northern Ireland 26 DCs Ages (102 period-cohorts) (A) Bto0, 0to1, 1to2, …, 99to100, 100+to101+ (102) Sexes (2) (S) Males, Females Ethnic Groups (18) (E) 15 from 2001 Census with “White: Other White-CEE EU” “White: Other White-Other EU” “White: Other-Other” Time intervals (flexible) (T) , …, , , …,

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Age Time x x+1 x+2 tt+1 lxlx l x+1 Survival probabilities and survivorship probabilities LxLx L x+1 sxsx pxpx

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Accounting framework for zones within countries School of Geography FACULTY OF ENVIRONMENT

School of Geography FACULTY OF ENVIRONMENT populations fertility mortality Internal migration International migration survival emigration migration conditional on survival within UK immigration Mortality assumptions Emigration assumptions Internal migration assumptions or model Immigration assumptions Projected deaths, survivors Projected surviving emigrants Projected surviving internal migrants final populations Projected surviving immigrants Projected final populations and births Fertility assumptions births Projection outputs Initial database scenarios

Ethnic mortality: proposed estimation method 1.LA life tables and LA SMRs for whole population Census SIRS for whole population 3.Compute SMR = a c + b c SIR for c=England, Wales, Scotland and Northern Ireland LAs Census SIRs for ethnic groups for LAs ethnic SMR e = a c + b c SIR e 6.d e a (1) = d * a SMR e 7.d e a (2) = d e a (1) × [D * a /Σ e d e a (1) P e a ] School of Geography FACULTY OF ENVIRONMENT

Internal migration model Something between a rock (saturated) O 434 D 434 E 18 S 2 A 102 and a hard place (independence) O D E 18 + S 2 +A 102 such as A 102 S 2 + O 434 D 434 E 7 + E 18 age-sex + origin-age, origin-destination- broad ethnicity + detailed ethnicity School of Geography FACULTY OF ENVIRONMENT

New Migrant Database Census NiNO WRS NHS PLASC With Country of origin to Ethnicity conversion School of Geography FACULTY OF ENVIRONMENT

We have been working on/will work on: Model design/program writing Initial database/completion and harmonisation Ethnic mortality/full implementation New migrant database/integration and synthesis Ethnic fertility/use of GHS and LS School of Geography FACULTY OF ENVIRONMENT