1 / 42

Introduction to the Census

Background on the nature of the Census and outline its importance todayProvide overview of the types and structure of the Census statistical outputsLook at Census geographyDiscussion of its limitations and strengths. Topics covered in this lecture. Introduction. OriginWhat's the point?Administrative issuesTaking stock Basis for economic and social policies?Scientific researchWhat is it? Any problems with it? .

gloria
Download Presentation

Introduction to the Census

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


    1. Introduction to the Census Introduction What is it? What is covered? Rationale for conducting a census UK Census Changing focus of the census The 2001 census Census output Census geography Problems with the census Conclusion: Limitations and strengths Appendix: Access to the data

    2. Background on the nature of the Census and outline its importance today Provide overview of the types and structure of the Census statistical outputs Look at Census geography Discussion of its limitations and strengths Topics covered in this lecture

    3. Introduction Origin What’s the point? Administrative issues Taking stock Basis for economic and social policies… Scientific research What is it? Any problems with it?

    4. What is a Census? The Census is a simple questionnaire survey administered by the government to all people in the UK on a single day Aim: Total enumeration of the population (i.e. a complete head count) at a single point in time Unique survey that provides national coverage Collects factual (‘objective’) data, not subjective opinions Self-completion and self-identification of the ‘facts’ Problem whether people fill it out accurately, subject to their interpretation of questions, do they lie?

    5. Subjects covered by the Census Demographic characteristics (age, sex, martial status) Household relationships Household accommodation Migration Employment Work place Journey to work Education and qualifications Health, provision of care Cultural characteristics Ethnicity Language Religion Seeking ‘facts’, not opinions or feelings

    6. Rationale for the Census Best picture of the state of people, households and homes in the UK Describes all people with uniform, consistent levels of accuracy Simple questionnaires are translated into large number of derived statistics

    7. Rationale for the Census Vital for policy analysis and used directly in calculating the allocations of billions of pounds of public expenditure (Ł60 billion figure quoted) Used to determine grants to local authorities and health trusts Census results have real world consequences Census “is still the bedrock of many a consumer research sample and the skeleton on which the numerous commercial classifications … are constructed.” retail planning, target marketing The Census is the most important secondary data source for academic researchers, especially for geographers Describes the detailed demography for small areas across the whole country vital for quantitative geographic analysis No other data sources provides such comprehensive spatial coverage.

    8. Rationale for the Census Construction of flow data Movements of people between small areas Commuting patterns Migration patterns Used to explore the nature of relationships between demographic and socio-economic variables across space It is the bench mark for other sample surveys (a kind of ‘gold standard’) Important in calculating statistical rates (provides denominator) Mortality rates Disease rates Unemployment and employment rates Census variables are combined to indices of deprivation

    9. Census and confidentiality Vitally important to protect personal information The Census forms are collected and processed in secure conditions. The Census Confidentiality Act 1991 gives legal protection by making the unauthorised disclosure of personal Census information a criminal offence (i.e. you will go to prison if violated) Same is true for Economic censuses, … Aggregation of individual values to a spatial scale where no personal identifiable data about an individual or household is discernible Statistical blurring of small counts in small area Individual data kept securely and only released after 100 years (1901 is now online) Think about how might need to guarantee anonymity to people you interview in your dissertation research

    10. UK Census Many countries carry out a national census (others do rolling surveys) UK Census is held every 10 years, at the start of each decade A Census has been held every decade since 1801 (except 2nd World War) 1801 Census 5 questions 10 million people living in 2 million households Rapid population growth and fear of overcrowding (‘Malthusian’ population crisis) 2001 Census 46 questions 60 million people 1901 Census is online and can search for your family, http://www.census.pro.gov.uk

    11. Changing focus of the Census

    12. The 2001 Census Most recent Census was held on 29th April 2001 Census 2001 revealed UK population was 58,789,194 Response rate was 95% Legally required to complete it (Ł1,000 maximum fine, but only 38 successful prosecutions) Very complex to plan, administer and to process and release data Estimated costs of Ł259 million Questionnaire design and wording thoroughly tested Temporary work force of about 70,000 people, inc. 62,500 census enumerators who hand deliver the forms Data entry and processing took over a year, some specialised results only released in 2004

    13. Innovations in 2001 Census Post back of the forms ‘One Number Census’ Imputation for people missed or did not complete a form 100% coding of the data from the forms. 1991 Census: much of detail was only coded for 10% sample Census access programme Free and easy access to all results, big contrast to previous years Much quicker release of results New structure of output geography based on postcodes (designed by geographer David Martin, University of Southampton)

    15. Was completed by all (or virtually all) 20+ million households in the country Needs to be as simple and clear as possible Self completed survey Quite short 10 household questions 36 individual questions 2001 Census questionnaire

    16. Tricky census questions No question on household income! Assumed it would scare people off or invite false answers Most important missing question Scientists want to include it for the 2011 (but unlikely) Preparations for the 2011 census already underway Religion question is optional as it is seen as somewhat controversial Campaign to get people to put down Jedi – 4th largest religious group in UK!) What might be some of the problems asking this question? What implications for areas/neighbourhoods Ethnic group membership question is problematic What does ethnicity mean? Health questions are problematic Subjective Potential for misuse of information by insurances,… How to complete free form answers? What other types of questions would you ask? Difficult to add new questions to the Census

    18. From questions to statistical counts From the individual answers a large number of cross tabulations are calculated to give individual variables or counts 40 questions generate 2 billion bits of data number of students in Camden (uni-variant count) number of students, by age groups (21-24, 25-29, etc) number of male students, by age groups 21-24, 25-29, Large number of possible cross-tabs Only a small number are calculated and published The cross tabulated data are aggregated to areas for publications

    19. Census data outputs printed reports national monitors and country reports topic based reports (e.g. housing)

    20. Area-based statistics Aggregated data are summarised in tables Each table covers a particular theme A table contains many predefined set of standard cross-tabulations of two or more variables Several types that vary in their level of detail number of topics number of cross-tabulation smallest spatial unit Trade-off between geographic and statistical detail (strict rules on confidentiality)

    21. Table types Standard Tables most detailed, 119 tables giving 75,000 variable. available for wards or larger units Census Area Statistics general purpose, 143 tables giving 15,000 variables. available for Census output areas and larger spatial units Key Statistics useful overview, 31 tables, 400 variables. available for Census output areas and larger spatial units Profiles overviews, aimed at particular users. available for parishes, parliamentary constituencies and postal sectors (WC1E 6) Headcount just a count of people, and households in each postcode

    26. Census geography

    27. 2001 census output units in England & Wales 42 counties (e.g. Inner London) 376 districts (Boroughs, e.g. Camden) 8868 wards (e.g Bloomsbury) 175,434 output areas (OAs) 80% contain between 110-140 households Census data are aggregated and made available for a number of geographical areas in England and Wales (things vary in Scotland) in 1991 including: counties, health authorities, local authority districts and also small areas known as wards and enumeration districts (EDs) (Cole, 1993). EDs were the basic building blocks used for the 1991 (and 1981) Census for both collecting and disseminating data. An ED contains about 200 households on average and is the smallest zone at which Census data are made available. EDs aggregate perfectly into wards, districts and finally counties at the top of the hierarchy, illustrated above in Box 3. In 2001 EDs were used for fieldwork and data collection purposes, whilst specially designed 'outputs' areas are being used for disseminating data. Census data are aggregated and made available for a number of geographical areas in England and Wales (things vary in Scotland) in 1991 including: counties, health authorities, local authority districts and also small areas known as wards and enumeration districts (EDs) (Cole, 1993). EDs were the basic building blocks used for the 1991 (and 1981) Census for both collecting and disseminating data. An ED contains about 200 households on average and is the smallest zone at which Census data are made available. EDs aggregate perfectly into wards, districts and finally counties at the top of the hierarchy, illustrated above in Box 3. In 2001 EDs were used for fieldwork and data collection purposes, whilst specially designed 'outputs' areas are being used for disseminating data.

    31. 32 Output Areas in Bloomsbury (24,140 Output Areas in London)

    32. Problems with the Census Census data goes out of date quickly Expensive (259 million Ł) Time burden on 50 million people Only “objective” facts Range of questions asked is limited (still no income question) Problems with comparison over time (changing questions, geography) People missing from the census (undercount)

    33. Census undercount People not counted (‘Missing millions’) 2% estimated to be missed by 1991 census Not evenly distributed through social groups or across space Westminster council claims to have ‘lost’ 65,000 people they expected Important as it effects the allocation of resources poorest areas tend to get hardest hit High non-response rates are found for: young people, especially men; students recent migrants unemployed minority ethnic groups private renters those who share a dwelling babies

    34. Census or senseless data ?? Can be confusing! Lots of boring technicalities Data itself is pretty boring But it is very useful as the data enables you to do interesting analysis Likely that many of you will want to use census data in your dissertations Be prepared to invest some time to find the right data, extract it and process it

    35. Conclusion: Strengths and weaknesses STRENGTHS ‘Gold standard’ data source Objective and consistent description of all people Geographically comprehensive data at range of geographical scales Consistent data for small areas Has the confidence of people and data users WEAKNESSES Census data goes out of date quickly. only once every 10 years Expensive Only “objective” facts Undercount) Limited range of questions Problems with comparison over time

    36. How can you access census data? published statistical summaries on http://www.statistics.gov.uk/census2001/census2001.asp full tables downloadable in Excel format from Neighbourhood Statistics website specifically for universities is the Census Dissemination Unit (CDU) at MIMAS (http://www.census.ac.uk/cdu) register & access for free using Athens account statistical data of the 1981, 1991 and 2001 Censuses through the CasWeb service Strict licensing agreements/undertakings govern all use of Census data and exist to protect individual privacy and crown copyright; for more information, see the Census Disseminaton Unit website. However, as long as you are studying or researching in an UK University or College, you can access Census data for free. Academic users can access the 1991 and 1981 census from MIMAS, using CASWEB or SASPAC Strict licensing agreements/undertakings govern all use of Census data and exist to protect individual privacy and crown copyright; for more information, see the Census Disseminaton Unit website. However, as long as you are studying or researching in an UK University or College, you can access Census data for free. Academic users can access the 1991 and 1981 census from MIMAS, using CASWEB or SASPAC

    38. Organisation of the UK census Census varies slightly in different countries of the UK. some different questions - language, religion, ethnicity Focus on England and Wales Sight variation in output census geography Some variation in the published census outputs

    39. More information on the Census

    40. www.chcc.ac.uk/CAS/resources.html

    42. Key reading for this Lecture (very useful for the course assessment!) Boyle P, Dorling D, 2004, “The 2001 census: remarkable resource or bygone legacy of the ‘pencil and paper era’? Area, 36(2) 101-110 download from http://www.geog.ucl.ac.uk/~jessletzbichler/geog2003/boyle_dorling2004.pdf

    43. Next week Monday: Exploratory data analysis - percentages, charts, histograms and correlation Tuesday: Census data analysis

More Related