Presentation on theme: "The micro-geography of UK demographic change 1991-2001 Paul Norman School of Geography, University of Leeds Understanding Population Trends and Processes."— Presentation transcript:
The micro-geography of UK demographic change 1991-2001 Paul Norman School of Geography, University of Leeds Understanding Population Trends and Processes ESRC RES-163-25-0012 for 2005-07 @ 40%
Main aim Quantify and map changes in population size and social characteristics which occurred in UK’s small geographical areas between the 1991 and 2001 Censuses Small area geography of reporting: wards & equivalents Population change Which demographic components account for change? Balance between natural change & migration change Area characteristics change Are areas becoming more or less deprived over time? Which area attributes change & why?
The micro-geography of UK demographic change 1991-2001 Population change Data preparation & number crunching: mostly completed Analysis: yet to be carried out Area characteristics change Data preparation & number crunching: partly completed LGA presentation Background Data problems & solutions Preliminary results
Use of area characteristics measures Cross-sectional research Allocation of funding Business marketing Deprivation relationship with health Time-series: deprivation measures Are areas becoming more or less deprived over time? Has regeneration policy been effective? Have patterns of unemployment changed? Has public housing gone into private ownership? Has health improved in areas now less deprived?
Background: Classification of areas Use of multiple input variables to produce a summary measure of an area’s characteristics Charles Booth, late 19th Century Human Ecologists, Chicago 1920s Social Area Analysis Factor Analysis / Principal Components Analysis Deprivation Indexes Geodemographics LocationDemographicHouseholdEmploymentEducationHealth Area 1 Area 2 Area 3
Classification of areas Problems when comparing areas at 2 (or more) time points Input data Availability, definition and categorisation Geography Boundary change Method of classification Applicability over time Need to compare like with like & need consistency of information, geography & method Otherwise comparisons invalid
Input data: availability, definition & categorisation Area classification using Census data 1991 & 2001 Topics & questions change Where available across time, tabulation categories vary More variables implies less consistency Large number of input variables too cumbersome Aim … Emulate deprivation indexes (e.g. 4 inputs) more realistic as a goal than geodemographics (e.g. 41 variables in ONS 2001 OA classification by Dan Vickers)
Input data Indexes widely used since 1980s Townsend indexCarstairs index Unemployment Male unemployment Household overcrowding No access to car Non-home ownership Low social class Townsend variables stable & comparable over time Carstairs Male unemployment too narrow Low social class misses/misclassifies people
Geography: small area boundary change Ward boundaries change to maintain sub-district equality in elector to councillor ratios Census data: smallest areas Enumeration Districts in 1991 a different geography to 2001 Output Areas Data collected & released for 1991 small areas cannot directly be compared with 2001 data
Geography: Ward boundary change Yellow wards in 2001 = no boundary change
Geography: Adjusting data between boundary systems Methods by ESRC funded research (Simpson 2002; Norman et al. 2003) Postcodes associated with 1991 EDs Postcodes associated with 2001 OAs Apportion data using weighted postcode distribution
Method of area classification Geodemographic cluster algorithms may be usable at two or more time-points to classify areas (more work needed) Are deprivation index methods usable across time? Input variables reveal each area’s situation relative to national level In 1991, is unemployment for area 1 more or less than England & Wales as a whole? Decide on national comparison level 1991, 2001 or an average
Deprivation 1991 & 2001 Townsend index Unemployment Household overcrowding No access to car Non-home ownership Data for 1991 EDs converted to 2001 OAs to capture sub- ward distributions, then aggregate to wards Calculate 1991 and 2001 indexes Comparison relative to 2001 levels
Deprivation 1991 & 2001 Less deprived 2001 average More deprived
Why has deprivation changed 1991-2001? Change at national level Unemployment 9% to 5% Household overcrowding2% to 1.5% No access to car27% to 22% Non-home ownership30% to 28% Local variations: yet to investigate Employment sector changes Tenure changes Regeneration schemes Database?
Effect of changing deprivation Limiting long-term illness 1991 & 2001 1991 2001 Is increasing deprivation over time associated with worse health?
The micro-geography of UK demographic change 1991-2001 Ongoing work … Population change Which demographic components account for change? Balance between natural change & migration change Area characteristics change Are areas becoming more or less deprived over time? Which area attributes change & why? Analysis for both to be done Area characteristics data preparation for Scotland and Northern Ireland