Post-Enumeration Survey – Requirements, Planning, Designing and Executing

1. Post-Enumeration Survey – Requirements, Planning, Designing and Executing Carlos Creva Singano, National Statistic Office, Mozambique -Maputo Adis Ababa Workshop 14-18 September 2009

2. 1. Requisite qualities of PES • All Census questionnaires must be returned from the field in all EA to National Statistic Office, before the PES field enumeration. • The processing of the PES data must be separate from the general Census of Population and Housing processing Data; • The PES staff must go to the field without knowing the preliminary results of the respective EA; • To take the advantage of General Census enumerators and supervisors, they must be used as the field staff;

3. 2. Costs /Other resources • The costs must be fixed based on the sample size, mainly at the first stage of sampling ( that is, nº of PSU to be selected) as well as the nº of Domains of Estimation; • The items to be included in the global cost are: -Transportation (Vehicles & its maintenance) - Field staff (PES enumerators; PES supervisors; PS Drivers); - Office Personnel (Matching clerks, matching Supervisors, Data Entry operators, Data Entry supervisors) - Printing and Reproduction (Questionnaires; Manuals, Maps, List of EA, etc)

4. 3.Organization structure/Technical planning • Depend on the Political and administrative structure: • Mozambique: - NSO (Central Level- Sample Design, Budget and its distribution by province according to the sample size); - Provincial Level ( Only for execution of the central directives; controlling the field staff and financial matters); To control the Quality in the enumeration in the dual system; • In Mozambique, the Province is a domain of estimation. The sample must be representative of strata within each province; • In each 11 Provinces, the NSO has a Provincial NSO for Operations issues.

5. 4.Procedure for Covarage analysis • There are Three Procedures for evaluation Census coverage in PES: Procedures A, B and C ( See Manual “ Evaluating Censures of Population and Housing”; • Mozambique used the procedure C, where the goal was to identify all current member of the sample HH as the 2007 PES date; in addition, any other resident as of the Reference Date of the General 2007 census of Population and Housing. • These persons are classified as either non-mover, out-mover and in-mover (that is, to identify immigrants and emigrants), with regard to their HH memberships status as of the 2007 Census Date. • In the 2007 Census records, only the Residents as the Date of the 2007 Census (the Non-movers and the Out-Movers), were matched.

6. 4. Procedure for Covarage analysis (Cont.) • 2007 PES Status Mozambique - Non-mover; - Out-mover; - In-Mover; - Bor After Some Definition: • Those who belonged to the HH as of the 2007 General Census and still as of the 2007 PES are the “Non-Movers”; • Those who became members of a different HH during the interim period between the 2007 General Census and the 2007 PES are the “Movers”. There are two types of Movers: • The “In-Movers” - those who arrived in the HH after 2007 Census; • The “Out-Movers” - those who have left the HH since the 2007 Census.

7. 4. Procedure for Covarage analysis (Cont.)(Some Definitions) • Persons who do not belong to the target population, that is, the population as of the 2007 Census date are considered “Out-of-scope”. This includes persons born after the 2007 census or persons who died before the 2007 Census,aliens and nonresidents. No match is attemted or Out-of Scope.

8. 5.Organization structure/Technical planning (Sample Size and Domain of estimation) • Depending on the main objectives to be measure (the coverage error or, the net omission rate), the geographic domains of analysis and financial resources, the sample size is fixed; • In Mozambique, the Domains of estimation are: Provinces; National and national Urban and national Rural; • The 2007 PES of Moz follow a Stratified Cluster sampling of 340 PSU: Minimal of 30 PSU by Province and Maxim of 40 PSU in Maputo, Capital of Mozambique. All unit of analysis (HH, persons, etc) in each sample PSU were interviewed; • Sample designing for 95 percent of Confidence;

9. 5.Sample Size and Domain of estimation (Cont.)

10. 5.Sample Size, Domain of estimation and estimates(Cont.) • Within each Province, the sample was stratified by urban and rural areas; • The Sample selection within each strata was selected independently with PPS. Measure of size was the nº of household within each strata; • Using the Dual system methodology (Procedure C), coverage and sampling errors were estimated. The national coverage error was 2.1 per cent. The Programme used were CENVAR (The IMPS Component) to main variables (eg, Age, sex, marital status, etc). • David Megill, The U.S.Census Bureau statistician, did help the Mozambican staff to do it;

11. 5. Sample Size, Domain of Estimation and estimates(Cont.) • 95 percent confidence intervals for the Census omission rate were estimated;

12. 6. Sampling Frame and Units of Analysis • Methodology of 2007 Moz PES: Two-way HHs and HHs Members; • The target universe included only the individual households in Mozambique; • Quarters groups were excluded of the scope; • The units of analysis in Mozambique 2007 PES were Households members

13. 6.Sampling Frame and Units of Analysis • Distribution of the HH in Mozambique by Province and area of residence. Preliminary Results

14. 6. Sampling Frame and Units of Analysis • Distribution of the PSU or EAS by Size oh HHs in Mozambique by Province and area of residence. Preliminary Results

15. 6. Sampling Frame, Units of Analysis, Sample Selection Methodology • The Sampling frame is stratified by Province Urban and rural; • The objective of this stratification is to improve the PES Sample Design; • The PSU or EA within each strata was selected by PPS. The number of HH within each was the measure of size. • An implicity stratification by political subdivision (OER Cod, CA_Cod and EA_Cod) was done before sample selection within each strata;

16. 7. Development of Questionnaire and field manuals • The Moz PES questionnaire was based on the final 2007 General census of Population and Housing Questionnaire; • The 1997 PES (Moz) and the 1991 PES (Ruanda) were used as Reference; • Demographics characteristics included in 2007 PES: • Marital status, age, sex and relationships to the head of the HH and • the section A of the General Census, that is, the location and area of residence of the HH to facility the matching process; • To facility the comparability between 2007 Census data and 2007 PES data, same response categories and precoding system were used;

17. 7. Development of Questionnaire and field manuals (Cont.) • To facility the field team (enumerators and supervisors), a small Manual with instructions, definitions was prepared; • The PES data collection aims were to identify all usual residents at the time of the 2007 Census in addition to those as of the date of the 2007 PES ( Procedure C in Slide 5-6).

18. 8. Budgeting/ Pilot test • The 2007 PES Budget Was planned as part of the 2007 census program; • The 2006 PES Pilot was care out to test theDual System methodology (Procedure C) of the 2007 Census of Population and Housing. This was done during the Pilot General Census of Population and Housing in 2006;

19. 9. Selection and training of field staff/ data collection • To take the advantage of 2007 General Census enumerators and supervisors, those were used as the field staff of 2007 PES; • They were trained during two days in each province. • The 2007 PES data collection did take place 15 days after 2007 General Census data collection. The objective was to minimize the matching difficulties processes related to the changes to the composition of the HHs between the two Dates.

20. 10. Omission rates for 2007 Census of Population and Housing

21. End Kanimambo