Definitions
Article 2
The definitions and technical specifications set out in Regulation (EC) No 763/2008 and Commission Regulations (EC) No 1201/2009 ( 2 ) and (EU) No 519/2010 ( 3 ) shall apply for the purpose of this Regulation. The following definitions shall also apply: 1. ‘statistical unit’ means the basic observation unit, namely a natural person, household, family, living quarter, or conventional dwelling; 2. ‘individual enumeration’ means that information on each statistical unit is obtained so that their characteristics can be recorded separately and cross-classified with other characteristics; 3. ‘simultaneity’ means that the information obtained in a census refers to the same point in time (reference date); 4. ‘universality within a defined territory’ means that data are provided for all statistical units within a precisely defined territory. Where statistical units are persons, ‘universality within a defined territory’ means that data are provided which are based on information for all persons that have their usual residence in the defined territory (total population); 5. ‘availability of small-area data’ means the availability of data for small geographic areas and for small groups of statistical units; 6. ‘defined periodicity’ means the capacity to conduct censuses regularly at the beginning of every decade, including the continuity of registers; 7. ‘target population’ means the set of all statistical units in a defined geographical area at the reference date which qualify for reporting on one or more specified topics. The target population includes each valid statistical unit exactly once; 8. ‘estimated target population’ means the best available approximation of the target population. The estimated target population consists of the census population plus under-coverage minus over-coverage; 9. ‘census population’ means the set of statistical units which is factually represented by the census results on one or more specified topics for a specified target population. The data records for the census population are the data records in the data source for the specified target population, including all imputed records and excluding all deleted records. If a data source comprises, as a matter of methodological principle, data records for only a sample of the statistical units in its estimated target population, the census population comprises, in addition to the statistical units in the sample, the complementary set of statistical units; 10. ‘complementary set of statistical units’ means the set of those statistical units that belong to an estimated target population, but about which the data source contains no data records as a result of an applied sampling methodology; 11. ‘coverage assessment’ means a study of the difference between a specified target population and its census population; 12. ‘post-enumeration survey’ means a survey conducted shortly after the enumeration for coverage and content assessment purposes; 13. ‘under-coverage’ means the set of all statistical units that belong to a specified target population, but are not included in the corresponding census population; 14. ‘over-coverage’ means the set of all statistical units that are included in a census population used to report on a specified target population without belonging to that target population; 15. ‘record imputation’ means the assignment of an artificial but plausible data record to exactly one geographical area at the most detailed geographical level for which census data are produced, and the imputation of that data record into a data source; 16. ‘record deletion’ means the act of deleting or ignoring a data record that is included in a data source used to report on a specified target population, but does not report any valid information on any statistical unit within that target population; 17. ‘item imputation’ means the insertion of artificial but plausible information into a data record where the data record already exists in a data source but does not contain this information; 18. ‘data source’ means the set of data records for statistical units and/or events related to statistical units which forms a basis for the production of census data about one or more specified topics for a specified target population; 19. ‘register-based data’ means data that are in or originate from a register; 20. ‘questionnaire-based data’ means data that are originally obtained from respondents by the means of a questionnaire in the context of a collection of statistical data which refer to a specified point in time; 21. ‘register’ means a repository which stores information about statistical units and is directly updated in the course of events affecting the statistical units. 22. ‘record linkage’ means the process of merging information from different data sources by comparing the records for the individual statistical units and merging the information for each statistical unit where the unit to which the records refer is the same; 23. ‘matching of registers’ means a record linkage where all matched data sources are contained in registers; 24. ‘data extraction’ means the process of retrieving census information from information contained in a register and relating to individual statistical units; 25. ‘coding’ means the process of converting information into codes representing classes within a classification scheme; 26. ‘identifying variable’ means a variable in the data records in a data source or any list of statistical units which is used — to evaluate whether the data source (or list of statistical units) includes no more than one data record for each statistical unit, and/or — for a record linkage. 27. ‘capturing’ means the process by which collected data are put into a machine-readable form; 28. ‘record editing’ means the process of checking and modifying data records to make them plausible while at the same time preserving major parts of these records; 29. ‘generation of a household’ means the identification of a private household according to the household-dwelling concept as defined in the Annex to Regulation (EC) No 1201/2009 under the topic ‘Household status’; 30. ‘generation of a family’ means the identification of a family based on information on whether the persons live in the same household, but with no or incomplete information on family relationships between persons. The term ‘family’ is specified as ‘family nucleus’ in the Annex to Regulation (EC) No 1201/2009 under the topic ‘Family status’; 31. ‘unit no-information’ means the failure to collect any data from a statistical unit that is in the census population; 32. ‘item no-information’ means the failure to collect data on one or more specified topics for a statistical unit that is in the census population, while data on at least one other topic can be collected for that statistical unit; 33. ‘statistical disclosure control’ means the methods and processes applied in order to minimise the risk of disclosing information on individual statistical units while releasing as much statistical information as possible; 34. ‘estimation’ means the calculation of statistics or estimates using a mathematical formula and/or algorithm applied to the available data; 35. ‘coefficient of variation’ means the standard error (square root of the variance of an estimator) divided by the expected value of the estimator; 36. ‘model assumption error’ means an error due to assumptions underlying the estimation and containing uncertainty or lack of detail; 37. ‘data structure definition’ means a set of structural metadata associated with a data set, which includes information about how concepts are associated with the measures, dimensions, and attributes of a hypercube, along with information about the representation of data and related descriptive metadata.