Planning and Implementation
of Post Enumeration Surveys
Pres. 4
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Some Requirements for a Good PES
 Adequate planning
 Technical personnel with requisite skills and experience in
survey methodology and in designing and implementing
the whole PES process
 Sample design, implementation, matching and estimation
 Develop an efficient sample design
 A successful PES calls for a good sample design and survey
implementation
 The timing of PES should be soon after census
 Maintain operational independence
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Some Requirements for a Good PES (Contd.)
 Ensure quality assurance in all the stages of the PES, thus
from planning to data processing
 Control of non-sampling errors is essential like in any
other surveys, as unlike sampling errors, they are difficult
to measure, therefore one is better off controlling them
 Credible estimation methodologies and procedures
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Planning of PES
Judicious planning for the PES is critical in
order to yield reliable results
Planning of PES should be:
 Preceded by a clear and unambiguous
statement of objectives as this facilitates to
articulate planning of PES activities
 Synchronized with planning for the census
 Start early and adequate resources devoted
to it as part of overall census programme
Develop a comprehensive survey plan showing
budgetary and manpower requirements
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Planning of PES (contd.)
Adequate Resources:
Financial allotment: Without sufficient funds
the PES would be poorly implemented and
therefore may not produce better results than
the census. This would defeat the whole
purpose of evaluating a census
Human resources: There is need to have
requisite number of specialist staff such as
survey methodologists; demographers; and
analysts; qualified enumerators and
supervisors
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Planning of PES (contd.)
 Commitment to the philosophy of a PES: it is very
critical to have the top management of a statistical/census
office committed to the philosophy of the PES, so that they
can plan for resources and support its efficient
implementation
 Establishment of an independent unit: It is advisable
that an independent PES planning and implementation unit is
established. This also enhances the operational
independence between the census and PES
 Technical planning: It is necessary to have sub-technical
teams to work on the sample design; plan for the
implementation of the PES; the design of a Dual System of
Estimation plan, matching and the reconciliation exercise
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Planning of PES (contd.)
Elements of planning a PES
Preparatory activities
Data collection related activities
Matching
Reconciliation (if undertaken)
Data processing
Estimation of coverage and content error
Report preparation and dissemination
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Planning of PES (contd.)
Publicity campaign
PES as a specialized data collection
Importance of not biasing potential sample
population
Strategies used in different countries(??)
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Implementation of PES
Pilot Test
This can be a dress rehearsal of the actual PES as
the pilot census is a dress rehearsal of the census
It can be conducted in selected administrative
divisions (taking into account costs)
The purpose of the pilot test is to test the
adequacy of the entire PES plan and its
organization
It should be conducted in conditions similar to the
actual enumeration of the actual PES
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Implementation of PES (contd.)
Pilot Test (Contd.)
The pilot test should follow immediately the census
pilot test
While it is not a source of usable data it provides
insights into operational aspects of data collection
that can contribute to a successful conduct of a
PES and census
Ideally it should be taken a year before the actual
PES just as a pilot census is taken a year before a
census (UN, 2008 P&R)
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Implementation of PES (contd.)
Pilot Test (Contd.)
Provides an opportunity to test questions and the
overall field methodology before mounting the PES
It also offers a chance to test the matching and
analytical procedures
Results of the pilot test contribute to establishment
of matching rules, reconciliation procedures and
logistical flows of documents between PES and
census
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Implementation of PES (contd.)
Data collection
Method commonly used in a PES is the face-to-face
interview
Enumerators go to households, in selected
EAs/clusters, and interview respondents
They collect information by asking questions from a
PES questionnaire
This method provides an opportunity for probing
Enumerators can explain the objectives of the PES to
respondents
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Implementation of PES (contd.)
Questionnaire
 Should be based on the final census questionnaire
 The format and size of questionnaire are important for
recording of responses and for data capture
 Pre-testing of questionnaire is imperative
 Selection of items for the questionnaire deserves careful
consideration
 Items to be used in matching process should ideally be
considered for the questionnaire
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Implementation of PES (contd.)
Questionnaire (Contd.)
 Variables for which information is to be collected on the
PES should have been included on the census as well
 Commonly considered variables include – age, sex,
relationship to reference person, marital status,
educational level and type of housing unit
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Implementation of PES (contd.)
Selection and training of field staff
Enumerators are the interface with respondents
 should be able to communicate effectively with
respondents
Their work is critical to the success of the PES field
work and therefore their selection is critical and
should be done objectively
They should be thoroughly trained before being
assigned field work
Main objective of training is to enhance uniformity
and minimize measurement error during interviews
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Implementation of PES (contd.)
Training
Qualified instructors well versed with the objectives
of the PES should be responsible for training
It is advisable that the trainers should be part of the
PES planning and implementation teams
Trainees should take turns in explaining to others
various items in the questionnaire
Practical lessons are essential both in the classroom
and the field. Based on performance trainees can be
retained as enumerators or dismissed
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Implementation of PES (contd.)
The role of supervisors
Despite good training of enumerators, without good
supervision, in the field, there may be inaccurate results
Need for dedicated and effective supervision
Supervisors should be more experienced and better
qualified than enumerators
Like enumerators, they should undergo extensive
training in all aspects of the PES
Supposed to organize work for enumerators by
determining field assignments
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Implementation of PES (contd.)
The role of supervisors (Contd.)
They review completed work and maintain a high
commitment of enumerators to the PES
A supervisor can make follow-up visits to nonrespondents as they are better qualified and
experienced
There should be a manageable ratio between
enumerators and a supervisor (1 to 5 ratio should be
okay)
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Implementation of PES (contd.)
Field data collection
During data collection objective is to classify
individuals by enumeration status relative to census
night
Use of probing is necessary to adequately establish
census night residence status
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Planning of PES (contd.)
Reconciliation (if done)
 Developing instructions for field reconciliation visits
 Training of enumerators and supervisors
 Carrying out reconciliation visits
 Final decisions on unresolved cases with respect to final
status
Data processing
 Selection or development of computer programmes for
data processing, tabulation & estimation
 Recruitment and training of data processing staff
 Carrying out data entry, editing and tabulation
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Planning of PES (contd.)
Estimation of coverage and content error
(i) Estimation of coverage error
(ii) Estimation of content error
Report preparation and dissemination
(i) Analysis of PES results including producing and
interpretation of sampling errors for key variables
(ii) Preparation of PES analytical report
(iii) Dissemination of results
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Implementation of PES (contd.)
Control of non-sampling errors
Should be controlled and reduced to the level that
their presence does not compromise the usefulness
of the PES results
Particularly harmful when they are non-random
because they introduce bias in the PES estimates
Bias is difficult to measure
Best way to control non-sampling error is to follow
the right procedures in all PES activities
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Implementation of PES (contd.)
Control of non-sampling errors (Contd.)
Should be controlled and reduced to the level that
their presence does not compromise the usefulness
of the PES results
Particularly harmful when they are non-random
because they introduce bias in the PES estimates
Bias is difficult to measure
Best way to control non-sampling error is to follow
the right procedures in all PES activities
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Implementation of PES (contd.)
Factors contributing to non-sampling error
Vague objectives of the PES
Duplication or omissions due to imprecise definition of
boundaries of EAs
Inappropriate methods of interviewing
Lack of trained and experienced field interviewers and
supervisors
Inadequate identification particulars of sampling units
Errors occurring in data processing
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010
Thank You!
United Nations Regional Workshop on the 2010 World Programme on Population and Housing Censuses:
Census Evaluation and Post Enumeration Surveys, Bangkok, Thailand, 10-14 May, 2010