Post-enumeration Survey (PES) - Statistics South Africa

Statistics South Africa
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Adjusted census population =
Adjusted 'Population within in-scope sub-universe'
+ Unadjusted 'Balance of population'.
It is worth noting that PES adjustment factors were based on the original geographic and demographic
classifications of persons. For geography type and EA type, 'original' referred to the classification in the
Census 2011 frame, before EA type changes occurred. For living-quarters type and for demographic
variables, 'original' refers to these variables as originally reported in the census.
Therefore, to maintain compatibility between the distribution of PES cases and census cases, the
original classifications (i.e., unedited or 'raw' data before editing and imputation) were used to decide
which factor a person would receive. Thus, census persons received the adjustment factor
corresponding to their original geography type and EA type, original living-quarters type, and original
sex/age group/population group cell. Once the adjustment factors were applied, persons and households
were permitted to shift to post-editing classification cells (which render census data more accurate and
more meaningful), but they carried their original adjustment factors individually into their new cells.
5.6 Content evaluation for persons
Content analysis is discussed in Section 8.1. The following must be noted regarding the use of the PES
for the measurement of content error:
• It is limited to matched cases.
• It is limited to the in-scope sub-universe, consisting of dwelling units and hostels within in-scope EA
types.
• The PES is not assumed to provide the 'truth'; therefore, response bias is not measured, only
response variance.
• Comparison is of unedited PES and census socio-demographic responses. (PES socio-demographic
data are not subject to edit; census data are, but these edits take place outside the PES.)
• Unlike the census and PES questionnaires in the PES sample, data capture for the full census was
not by key-from-paper but by scanning with rigorous quality control. In addition, census data were
later subject to an intensive edit and automatic-correction process. Hence, to a certain extent, the
data quality in the published census results is improved over what is indicated by the content analysis.
It was also noted in Section 8.1 that the estimated person totals shown in the content analysis tables do
not coincide with the final census totals for each characteristic because:
• they are based on the sample of census records in the PES and are, therefore, subject to sampling
variability;
• they include only matched cases, not the full sample;
• they are unedited while the census characteristics are edited;
• they include only the in-scope sub-universe while the final census totals include the full universe; and
Post Enumeration Survey (PES)