Post-enumeration Survey (PES) - Statistics South Africa

Statistics South Africa
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7. COVERAGE EVALUATION OF HOUSEHOLDS
7.1 Estimation of true population
The same dual-system estimation procedure described for persons in Section 5.1, and explained in
detail in Section 5.3, was applied to households.
In Census 2011, a 'household' corresponds to the collection of persons in one set of questionnaires
(including continuation questionnaires). 'Questionnaire' (parent questionnaire coupled with continuation
questionnaires) and 'household' thus refer to the same set of persons. Even though the basic definition
for household is similar in both the census and PES, there are conceptual differences because the
'questionnaire' is not a fixed entity in the universe: the number of questionnaires completed for one
housing unit can vary from interview to interview, especially in de facto enumerations which are based
on presence rather than usual place of residence.
Figure 14: Estimates of total households from individual systems and from the dual system – inscope
sub-universe
1. Census enumerated
total HHs
11,67 million
2. PES estimate of total HHs
11,32 million
3. Preliminary dualsystem
estimate of
the true total of HHs
13,89 million
In the sub-universe in scope for the PES, the separate census and PES enumerations produced 11,32
million and 11,67 million households, respectively. Using the dual-system estimation method, the true
household total of South Africa in the in-scope sub-universe was estimated at 13,89 million. Four
components together make up the dual-system estimate of the true population.
Post Enumeration Survey (PES)