1. Methodologies and Procedures for Evaluating Coverage and Content Error Pres. 6
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses: Census Evaluation and Post Enumeration Surveys, Addis Ababa, Ethiopia, September 2009

2. Methodologies & Procedures for Evaluation
PES basically involves two overlapping P- and E- samples
P sample areas disclosed only need to know basis
P and E samples data collection occurs at different times
Mover procedures A, B, & C
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses: Census Evaluation and Post Enumeration Surveys, Addis Ababa, Ethiopia, September 2009 2

3. What is a P sample?
The Population (P) consists a sample of clusters drawn from the same population but independent from the census
Independently listed units that are valid and unique
Results used to estimate census omissions
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses: Census Evaluation and Post Enumeration Surveys, Addis Ababa, Ethiopia, September 2009 3

4. What is an E sample?
The E sample is a sample drawn from cases already enumerated in the census
Housing units enumerated in the census in the same sample area as the P-sample
It is not uncommon to have an overlap of the E and P samples
Results used to estimate census erroneous inclusions
Estimate of erroneous inclusions provides a correction factor used in the Dual System Estimate of True Population
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses: Census Evaluation and Post Enumeration Surveys, Addis Ababa, Ethiopia, September 2009 4

5. Some definitions
Non-movers: persons who were in a particular household as of the census and PES date
Out-movers: persons who were in a particular household at the census date but moved out or were not part of the household at the time of the PES
In-movers: Persons who were enumerated in a particular household during the PES but where not there during the census date
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses: Census Evaluation and Post Enumeration Surveys, Addis Ababa, Ethiopia, September 2009 5

6. Census date PES date Mary Paul John Mary Paul Peggy Peggy John
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses: Census Evaluation and Post Enumeration Surveys, Addis Ababa, Ethiopia, September 2009

7. Census date PES date Mary Paul John Mary Paul Peggy Peggy John
Non movers
Mary
Paul
John
Mary
Paul
Peggy
In mover
Out mover
Peggy
John
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses: Census Evaluation and Post Enumeration Surveys, Addis Ababa, Ethiopia, September 2009

8. Measuring Omissions & Erroneous Counts
Procedure A
Constructs households as they existed at the time of the census
Respondents asked to identify all persons in sample households on census date
Persons are subsequently matched against names, addresses or locations on census records
Estimates are then made of numbers and percent of matched non-movers and out-movers
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses: Census Evaluation and Post Enumeration Surveys, Addis Ababa, Ethiopia, September 2009 8

9. Census date Procedure A PES date
Mary
Paul
…John
Mary
Paul
John
Mary
Paul
Peggy
Peggy
John
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses: Census Evaluation and Post Enumeration Surveys, Addis Ababa, Ethiopia, September 2009

10. Measuring Omissions & Erroneous Counts (contd.)
Procedure B
Identified all current residents in sample households at the time of PES
Respondent asked to provide address(es) or location(s) where they were on census date
Then matched against names on corresponding census questionnaires
Estimates of number and per cent matched for non-movers and in-movers are calculated
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses: Census Evaluation and Post Enumeration Surveys, Addis Ababa, Ethiopia, September 2009 10

11. Census date Procedure B PES date
Mary, Paul
Peggy
Mary
Paul
John
Mary
Paul
Peggy
Peggy
John
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses: Census Evaluation and Post Enumeration Surveys, Addis Ababa, Ethiopia, September 2009

12. Measuring Omissions & Erroneous Counts (contd.)
Procedure C
Identifies all current residents living at the same address at the time of PES
Also identifies persons who lived at the sample address during the census date
Only census date residents (non-movers and out-movers) are, however, matched with census records
Estimates are calculated of non-movers, out-movers, in-movers, of the per cent matched for non-movers & out-movers
Procedure C is a combination of procedures A & B
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses: Census Evaluation and Post Enumeration Surveys, Addis Ababa, Ethiopia, September 2009 12

13. Census date Procedure C PES date
Mary, Paul
Peggy …John
Mary
Paul
John
Mary
Paul
Peggy
Peggy
John
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses: Census Evaluation and Post Enumeration Surveys, Addis Ababa, Ethiopia, September 2009

14. Strengths and Weaknesses of Procedure A
Advantages
Matching of non-movers and out-movers relatively simple and inexpensive – searches limited to sample areas and their adjacent areas
Limitations
Out-movers no longer at the sample address
Getting information from proxy respondents difficult especially where the whole household moved
Susceptible to underestimation of out-movers and omissions
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses: Census Evaluation and Post Enumeration Surveys, Addis Ababa, Ethiopia, September 2009 14

15. Strengths & Weaknesses of Procedure B
Advantages
Field procedures simpler
Provides better estimates of movers
Limitations
Higher cost of matching as it involves in-movers being identified within areas where they were during the census
The above may result in extended matching because clusters (EAs) may not be in PES sample – more of a problem where addresses are lacking or inadequate
Not sure whether failure to match means an actually omitted person or incorrectly located
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses: Census Evaluation and Post Enumeration Surveys, Addis Ababa, Ethiopia, September 2009 15

16. Strengths and Weaknesses of Procedure C
Advantages
Method takes advantage of strengths of both procedures A & B
Reduced matching difficulties
Improved estimation of movers
Limitation
Relatively expensive, requires enumeration of in-movers, out-movers and non-movers
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses: Census Evaluation and Post Enumeration Surveys, Addis Ababa, Ethiopia, September 2009 16

17. Thank You!
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses: Census Evaluation and Post Enumeration Surveys, Addis Ababa, Ethiopia, September 2009