1. Estimating breaks in time series in the Austrian LFS
Judith Forster
Daniela Gumprecht
Statistics Austria
Reykjavík, Iceland
18 May 2018

2. Breaks in Time Series (BiTS)
1. The BiTS-project
2. The pilot survey
3. The statistical models
4. The impact factors
5. The communication strategy

3. 1. The BiTS-project Starting point:
IESS Framework regulation & 19th ICLS resolution
Objective:
Break free time series for 14 indicators
Methods:
Pilot survey
Statistical models

4. 1. The BiTS-project Starting point:
IESS Framework regulation & 19th ICLS resolution
Objective:
Break free time series for 14 indicators
Methods:
Pilot survey
Statistical models
The break will be…

5. 1. The BiTS-project
How to deal with changes lying within the confidence intervals?
Estimates and confidence intervals for the 14 indicators, for which break factors will be provided.
Source: Statistics Austria, Labour Force Survey, Q2 2017, n = 8,640,465
Indicators:
Employed/Unemployed
by age group
Women
Men
Estimates
Confidence interval 2.5%
Confidence interval 97.5%
Employed
15–24
233,029
224,411
243,466
248,693
238,345
258,816
20–64
1,919,611
1,905,617
1,933,578
2,141,963
2,127,301
2,155,164
25–64
1,740,617
1,725,910
1,754,234
1,965,645
1,951,815
1,978,565
65+
29,269
24,308
34,194
43,177
36,978
50,360
Unemployed
19,759
14,647
23,900
27,582
21,649
33,127
83,252
74,844
91,869
110,895
101,867
121,209 -

6. 1. The BiTS-project
How to deal with changes lying within the confidence intervals?
Estimates and confidence intervals for the 14 indicators, for which break factors will be provided.
Source: Statistics Austria, Labour Force Survey, Q2 2017, n = 8,640,465
Indicators:
Employed/Unemployed
by age group
Women
Men
Estimates
Confidence interval 2.5%
Confidence interval 97.5%
Employed
15–24
233,029
224,411
243,466
248,693
238,345
258,816
20–64
1,919,611
1,905,617
1,933,578
2,141,963
2,127,301
2,155,164
25–64
1,740,617
1,725,910
1,754,234
1,965,645
1,951,815
1,978,565
65+
29,269
24,308
34,194
43,177
36,978
50,360
Unemployed
19,759
14,647
23,900
27,582
21,649
33,127
83,252
74,844
91,869
110,895
101,867
121,209 -

7. 2. The pilot survey Q1–Q4 2020 n = 6,000 households
Two waves: 1st wave CAPI, 2nd wave CATI
2020
Sample 1 Q1
1st wave
Sample 2 Q2
2nd wave
Sample 3 Q3 Q4
Four quarters overlap

8. 2. The pilot survey Sample size
Sample size of the regular LFS sample (Q1–Q4) and expected sample size for the pilot survey (Q1–Q4) by the 14 indicators, for which break factors will be provided.
Source: Statistics Austria, Labour Force Survey 2017
Indicators:
Employed/
Unemployed
by age group
Regular LFS sample (Q1–Q4) ~82,000 households; 178,997 persons
Pilot survey sample (Q1­–Q4) ~6,000 households; 13,668 persons
Women
Men n %
Employed
15–24
4,658 49
5,298 53
337
414 52
20–64
40,726 73
44,213 82
3,114 72
3,320 81
25–64
37,399
40,689 83
2,874
3,056
65+
665 3
1,025 7 59 5
424 4
496 29 32
1,414
1,568
111
123 2 - 1

9. 2. The pilot survey Sample size Oversampling is necessary!
Sample size of the regular LFS sample (Q1–Q4) and expected sample size for the pilot survey (Q1–Q4) by the 14 indicators, for which break factors will be provided.
Source: Statistics Austria, Labour Force Survey 2017
Indicators:
Employed/
Unemployed
by age group
Regular LFS sample (Q1–Q4) ~82,000 households; 178,997 persons
Pilot survey sample (Q1­–Q4) ~6,000 households; 13,668 persons
Women
Men n %
Employed
15–24
4,658 49
5,298 53
337
414 52
20–64
40,726 73
44,213 82
3,114 72
3,320 81
25–64
37,399
40,689 83
2,874
3,056
65+
665 3
1,025 7 59 5
424 4
496 29 32
1,414
1,568
111
123 2 - 1
Oversampling is necessary!

10. 3. The statistical models
old LFS
new LFS
Forecast of
the old LFS
Register data

11. 4. The impact factors new LFS Pilot survey Impact of the break old LFS
Forecast of the old LFS
old LFS
Register data
Impact of the break

12. 5. The communication strategy
Time series
Break
New regulation
Consequences
Reasons
Impact Factor
Communicaton for BiTS …coming soon.

13. 5. The communication strategy
Good practise example: New weighting procedure 2015
Revision of microdata and back calculation until 2004
Methodological report
Frequently Asked Questions (FAQs)
Press conference
Internal and public presentations
Paper published in the Austrian Journal of Statistics

14. Thank you! I see a break Please address queries to: Judith Forster
Daniela Gumprecht
Contact information:
Guglgasse 13, 1110 Vienna
phone: +43 (1)
I see a break
Thank you!