Transcript PPT

Annual labour force surveys
Ralf Hussmanns
Head, Methodology and Analysis Unit
Bureau of Statistics
International Labour Office
International recommendations on
periodicity of labour force statistics
“Current statistics of the economically
active population, employment, where
relevant unemployment, and where
possible visible underemployment, should
be compiled at least once a year.”
 ILO Recommendation No. 170 (Labour
Statistics Recommendation), 1985,
Paragraph 1. (1)
International recommendations on
periodicity of labour force statistics
“The current statistics programme should
encompass statistics of the currently
active population and its components in
such a way that trends and seasonal
variations can be adequately monitored.
As a minimum programme, countries
should collect and compile statistics on
the currently active population twice a
year … ”
 13th ICLS (1982), Paragraph 2 (a)
International recommendation on
periodicity of statistics on the
informal sector
“The data collection programme should
provide both for (a) the current
monitoring, if possible once a year, of the
evolution of employment in the informal
sector and (b) the in-depth examination,
if possible every five years, of informal
sector units with respect to their numbers
and characteristics ...”
 15th ICLS (1993), Paragraph 21 (1)
Annual labour force surveys
Periodic data collection (point in time
 once a year
 two, four or twelve times a year
Continuous data collection (annual,
quarterly or monthly averages):
 every week
Continuous data collection (1)
Seasonal and other variations over time are
captured and period effects eliminated through
division of sample in monthly, fortnightly or
weekly sub-samples and continuous data
collection during the year (examples: Mauritius,
South Africa).
 Estimates reflect the average situation during a
month, quarter or year, i.e. for many purposes
(including national accounts) they are more
useful than point-in-time estimates.
Continuous data collection (2)
Flexibility in periodicity of data dissemination
(example Colombia: dissemination of monthly,
bi-monthly, quarterly, bi-annual and annual
 but inverse relationship between (i) level of
geographic and other detail of estimates and (ii)
frequency of data dissemination.
 It becomes unnecessary to use concepts based
on long reference periods (e.g. usual activity,
annual income), which are prone to recall
Continuous data collection (3)
As data entry and processing can be carried out
on a continuous basis, the time lag between data
collection and dissemination can be much
reduced (South Africa: one month) and the users’
demand for more timely statistics be satisfied.
Data quality is improved because field work is
carried out by small teams of permanent
interviewers and supervisors (reduced cost &
improved quality/intensity of training,
recruitment and supervision of field staff
facilitated, including re-interview programme).
Additional topics can be included in the survey as
modules attached to it from time to time.
Enhanced flexibility to meet
demands for additional data
Additional topics included in the survey should
be somehow related to the core topics of the
 to avoid that the survey will become an omnibus
multi-purpose survey.
 Not all additional topics require to be
investigated in using the whole sample.
 To reduce response burden and survey costs,
sub-samples can be used to investigate various
additional topics.
Defined by rotation groups
 or determined by serial number of the
 or representing all households interviewed
during a specific period of time (month,
quarter or year)
Determining factors for type
of sub-sample
Urgency of user needs for the information, time
available for data collection.
Nature of the topic, especially its being subject
or not to seasonal or other variations over the
Usefulness of inclusion of topic in repeated
interviews of the same households.
Precision requirements for estimates.
Response burden of households.