Post-enumeration Survey (PES) - Statistics South Africa

Statistics South Africa
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• There is independence between census and PES, i.e. the organisation of the census and PES,
especially fieldwork operations, must be managed by different teams.
• There is absence of erroneous inclusions in either the census or PES.
• There are no incomplete matches. Any failure to match census and PES items should be due to
actual omission and not the inability to match.
There are three alternative procedures for evaluating census coverage in a PES. These three
procedures are known as A, B, and C (see Annexure A for definition of terms).
Procedure A
• Seeks to reconstruct the households as they existed at the time of the census.
• The respondent must identify all persons in the sample household on the census reference date.
• The aim is to match these persons (non-movers and out-movers) to the census questionnaires, and
to estimate the number and percentage of matched non-movers and movers (out-movers).
• The matching of non-movers and out-movers is relatively simple and inexpensive because the
search is limited to sample areas, but it is difficult and expensive to locate out-movers, especially
out-mover households, given that they are no longer at the sample address (information, when
available, is reported by proxy respondents), hence, there is a strong possibility of underestimation
of the number of movers (out-movers).
• This leads to underestimation of the census omissions.
Procedure B
• Seeks to identify all persons in the sample household on the reference date of the PES.
• People respond for themselves; hence field enumeration is more complete than in Procedure A.
• The aim is to match these persons (non-movers and in-movers) to the corresponding census
records and to estimate the number and percentage of matched non-movers and movers (inmovers).
• It provides a better estimate of the number of movers than Procedure A, but associated difficulties
and costs of matching are far greater because it involves searching for in-movers in the area where
they were enumerated during the census.
• It is not sure if failure to match means an actually omitted person or an incorrectly located person.
• This leads to overestimation of the census omissions.
Post Enumeration Survey (PES)