GEOG3025 Census and administrative data 1: Sources and methods

GEOG3025 Census and administrative data Lecture overview Objectives of lecture Social data entities Social data sources Questions Census and administrative data sources and processing Lecture summary

GEOG3025 Objectives Understand the variety of social entities in which we may be interested Recognise the key data sources and their characteristics Understand the processes by which these data sources are processed to create data outputs

GEOG3025 Social data entities What is the elemental information unit in which we are interested? –Neighbourhood (definitional issues) –Dwelling unit –Household –Person –Event (e.g. birth, death, hospital admission, etc.)

GEOG3025 Attribute detail Ease of access Level of aggregation Censuses Surveys Admin records Low High

GEOG3025 Administrative records Population registers (esp. Scandinavia) Registers maintained for the purposes of delivering a service –Driven by specific organisational needs Few attribute details unless maintained as statistical register, but timely Aggregated for output, but not at source

GEOG3025 Population censuses Aggregate data but available for small areas High coverage rates but limitations of census questions (health, income, etc.) Cross-tabulated to full range of socioeconomic characteristics Infrequent (decennial) Multiple data outputs

GEOG3025 Social survey data Even largest surveys cover only small proportion of population –Sampling error and small number problems Advantage of timeliness Geographical coverage difficulties Potentially high levels of attribute detail and cross-tabulation possible

GEOG3025 Introductory questions… What do we mean by ‘administrative’ data? How do the census questionnaire responses become data? Are the data reliable anyway?

GEOG3025 Administrative sources Population register (Netherlands, Denmark, etc.) National health service register (NHSCR) Electoral register Council tax register Hospital episodes system (HES) Inland revenue database Customer databases (loyalty cards, etc.)

GEOG3025 LA register extract UPRN RV TYPE ADDRESS FIELDS N’hood (3) Street (4) Num (4)

GEOG3025 Neighbourhood Statistics Government departments contributing datasets derived from administrative records Aggregating initially to 1998 wards, soon to be super output areas (SOAs) Varying levels of SOA reflect sensitivity of different administrative datasets

GEOG3025 NeSS

GEOG3025 Neighbourhood Statistics

The 2001 census process… Address pre-listing Enumeration Census 29 April 2001 Collection of forms Scanning of forms and creation of database Census Coverage Survey One Number Census processing Output creation

GEOG3025 Address listing

Enumerator’s map

Census field force Source: CHCC Unit 4Source: ons.gov.uk

GEOG3025 Collection and OCR Post-back of majority of forms Enumerators concentrate on forms not returned OCR at single processing centre Creation of database for checking and correction by census organisations Source: ons.gov.uk

GEOG3025 Census Coverage Survey Recognition of inevitable undercount Coverage survey of 300,000 households 4-8 weeks after census Intensive enumeration with no address pre-listing Stratified sample of postcodes – by LAD and hard-to-count index

GEOG3025 One Number Census Dual system estimator: attempts to match census and CCS responses Assess probabilities of being Imputation of missing households and missing individuals within households Modification of census database to produce ‘one number’ outputs Cross-check against admin sources

GEOG3025 Assignment 4 Work through CHCC unit 1 ‘A quick introduction to the census’ and unit 4 ‘Census 2001: the enumeration process’ Use NeSS to locate information about your chosen neighbourhood and retrieve attributes that particularly characterise that area

GEOG3025 Lecture summary Objects of interest Administrative, census and survey sources –Admin and censuses for neighbourhoods Administrative sources –Development of NeSS Census data processing