1. Nonresponse adjustments and calibration: a comparison between two methods to weight the Labour Force Survey
Tania Borg
Principal Statistician Labour Market and Information
Society unit
18 May 2018

2. Overview of Maltese LFS
Systematic random sample of 3,200
households
Panel survey 2-(2)-2
Weights
LFS is being adjusted for nonresponse in attrition using weighting classes
Post stratification on 5 year age groups, sex and NUTS 4

3. Problems encountered Under coverage in sampling frame
Unit nonresponse adjustments
Unrevised population estimates

4. Main scope Improve LFS estimates Treat under coverage problems
Upgrade current situation
Improve nonresponse adjustments
Treat under coverage problems
Improve LFS estimates
Main scope

5. Nonresponse adjustments
Methods tested
Method 1
Method 2
Design weights
Nonresponse adjustments
Calibration

6. Nonresponse adjustments
Proposed approach
Design weights
Probability of selection based on NUTS 4 and number of members in the household
Nonresponse adjustments
Unit nonresponse weighting classes – 10 year age groups, household size and nationality
Propensity models on attrition based on various LFS characteristics
Calibration
GREG estimation

7. Results

8. Results

9. Results

10. Results

11. Non-nationals estimates
Conclusion
Parallel
weights
DEFF and CV’s for Method 1 slightly higher
Comparable estimates
Differences rose with low sample counts
Increasing margin of error with time
Non-nationals estimates
Both methods gave unsatisfactory estimates for non-nationals
Method 2

12. Limitations Country and survey specific
No exact administrative source in Malta
Under coverage in sampling frame
Results may have varied if the difference between the sampling frame and benchmarks were minimal

13. Way Forward and other research
Further research on nonresponse bias
Simulation study
Address under coverage problems

14. THANK YOU FOR YOUR ATTENTION