1. Transition from traditional census to sample survey? (Experience from Population and Housing Census 2011) Group of Experts on Population and Housing Censuses, Geneva, 24.- 25. May 2012 Ľudmila Ivančíková, Viera Doktoríková Statistical Office of the Slovak Republic

2. Census 2011 – Basic info Traditional census based on self-enumeration Field workers – 19 756 enumerators Electronic and traditional questionnaires Using of identifiers Population Register used for generating the identifiers, as a tool for comparing the census results with the administrative source and as a base for imputations

3. Important dates - summary Census Reference date -> midnight between Friday, the 20th of May, 2011 and Saturday, the 21st of May, 2011 Census Period -> from May, 13th to June, 6th Data collection through the Internet -> May, 21st – May, 29th Data processing from -> June, 6th till now Final outputs on national level -> 2012 February 29th

4. Traditional census in Slovakia Long history of conducting censuses as a comprehensive survey (from 1754) Range of traditional elements from the previous censuses were applied: -institutional covering by regional statistical offices and municipalities -data collection by the means of field work -using of paper questionnaires

5. Public reaction – response burden Negative –> reason = multiple collection of basic demographic characteristics and personal data (for checking the identity of persons) Requests from the public – to use the administrative data sources (ADS) –> more accurate and updated data on the regular basis – almost immediately after the change of demographic or socio-economic characteristics has been made

6. Reasons for keeping the traditional form of census conducting Some but not all characteristics are available from registers Existing administrative sources contain data for particular group of inhabitants not for the whole population The unified identifier, which could make possible the two- way linking of data, does not exist yet The project of informatization of the public administration was stopped just after the adoption of census law act, although it could help use the ADS also for census purposes

7. Using ADS in the next census Precondition -> positive public opinion for using ADS for the statistical purposes and strong accent on the privacy protection Principle -> ADS provide the complete coverage and reduce the costs By using registers it is possible to produce more detailed statistics then by using sample surveys (e. g. small areas data or multiplied classifications) Legislation has to reflect the fact of using existing ADS besides the repeating data collection for the statistical purposes

8. Population Register (PR) as a source of data for the census Currently used for annual demographic balances processing Contains all necessary data besides the data on the educational attainment Possible complications: the quality of data in PR is not sufficient, but the problems are solvable just in a short-time horizon – there is no need for legislation changes, just for adjustment of output data from the PR on the base of external information and providing the data from Ministry of Interior on a regular basis

9. Problematic issues from the 2011 census Traditionally, the response rate and the completeness were very high, it was not an issue to solve In the 2011 census the rate of non-responses significantly increased in all three types of non- responses – per unit, partial per unit and item non- response In the case of the item non-response some of the relevant answers were not provided The unit non-response was geographically concentrated mainly to the location of the capital

10. Solutions for problems occured in 2011 Census The SO SR hired the external experts to work up the theoretical solutions, methods and software tools for using the imputations The data are currently in the processing phase, that contains also the data analysis and imputation

11. Future of the census conducting in Slovakia According to the current conditions, replacing the traditional census with administrative sources seems to be hardly probable Therefore we should look for a transitional form of census conducting – e.g. combination of traditional method and the sample survey Variables that could be included into the comprehensive (nationwide) survey and variables that could be surveyed in the sample surveys

12. Conclusions Development of IT opens the way for using ADS The process of transition should be gradual Preparation of the next census immediately after ending the 2011 Census Output presentation as a matter of discussion (how detailed information on which geographical level) Participation of all involved subjects The law act should be prepared with more respect of current situation and adopted as close as possible to the census reference date

13. Thank you for your attention.