Improving of Household Sample Surveys Data Quality on Base of Statistical Matching Approaches

1
Improving of Household Sample Surveys Data
Quality on Base of Statistical Matching
Approaches
The European Conference on Quality in Official
Statistics Rome, 8-11 July 2008

• Ganna Tereshchenko
• Institute for Demography
• and Social Research,
• Kyiv, Ukraine

2
Measurement of Employment and Unemployment

• Main source is The State Sample Survey of
  Economic Activity of Population (LFS)
• is conducted by State Statistics Committee of
  Ukraine
• by ILO methodology, according to
  international standards
• population in the age of 1570 years is surveyed
• is conducted since 1995 in 19951998 once a
  year,
• in 19992003 quarterly, since 2004
  monthly
• LFS sample cover all regions of Ukraine by type
  of settlements urban area (cities, towns) and
  rural area
• size of monthly LFS sample is 32,5 thousands of
  surveyed households

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Reliability of unemployment rate annual estimates
4
Improvement of reliability of LFS indicator
estimates for rural area based on statistical
matching approach

• Using of two probability stratified two stage
  samples sample of LFS and sample of household
  agricultural activity survey (AAS)
• Sample design in AAS is differ from LFS
• In AAS households are selected in the second
  stage with probability proportionally to their
  area of agricultural allotment, in LFS on base
  of the procedure of systematic selection
• The size of monthly LFS sample in the rural area
  makes approximately 3,6 thousand households
• The size of AAS sample of households which have
  to be interviewed under LFS questionnaire is 7,4
  thousand households
• Total size of monthly sample for interview under
  LFS questionnaire in the rural area due to AAS
  has increased three times and is equal to11,1
  thousand households

5
Rates of employment and unemployment by regions
of Ukraine, February, 2007
6
Composite estimation
7
Calculation of optimal weights coefficients
and

• where standard error of
  estimate of employed population number
  on LFS sample
• standard
  error of estimate of employed population number
  on AAS sample
• standard
  error of estimate of unemployed population number
  on LFS sample
• standard
  error of estimate of unemployed population number
  on AAS sample,
• is the bias of
  estimate of number of employed population by data
  of AAS, calculated as average of biases for
  current and the two previous months,
• is the bias of
  estimate of number of unemployed population by
  data of AAS, calculated as average of biases for
  current and the two previous months.

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Calculation of coefficients for adjustment of
the resulted employed and unemployed persons
weights in rural area

• On the first stage value of is calculated
  for employed and unemployed persons in rural area
  by the formula
• The corrected statistical weights of employed
  and unemployed persons in rural area of each
  region are calculated by the formula

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Calculation of coefficients for adjustment of
the resulted economically inactive persons
weights in rural area

• On the second stage value of is calculated for
  economically inactive persons in rural area for
  each region by the formula
• where total number of able-bodied
  population in rural area of region, calculated on
  external data
• estimate of
  employed population number on LFS sample in view
  of corrected statistical weights
• estimate of
  employed population number on AAS sample in view
  of corrected statistical weights
• estimate of
  unemployed population number on LFS sample in
  view of corrected statistical weights
• estimate of
  employed population number on AAS sample in view
  of corrected statistical weights
• estimate of
  economically inactive population number on LFSP
  sample in view of corrected statistical weights
  
• estimate of
  economically inactive population number on AAS
  sample in view of corrected statistical weights

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Reliability of employment rate monthly estimates
in rural area before and after statistical
matching of the LFS data, February, 2007
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Reliability of unemployment rate monthly
estimates in rural area before and after
statistical matching of the LFS data, February,
2007
12
Potential problem with comparability of
unemployment rate estimates by regions

• Share of incomparable estimates
• where number of regions

13
Relative efficiency of matching procedure by
regions, February, 2007
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Conclusions

• Statistical matching of the labour force survey
  data, received on samples with different design
  has allowed improving the reliability level of
  employment and unemployment indicators estimation
  in rural area.
• At the same time there is a potential problem
  with providing of data comparability
• It is necessary to take into account that the
  volume of the information for processing grows
  and estimation procedures are complicated

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Thank you for attention!

• Ganna Tereshchenko
• Institute for Demography and Social Research
• of National Academy of Sciences of Ukraine
• Kyiv, Ukraine
• a_tereschenko_at_ukr.net