Evaluation of the Australian Wage Subsidy Special Youth ...

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5.6 Accounting for non-response and sample design
In the analysis so far, only sample reduction subsequent to the 1984 survey has been
considered. It is however pertinent to ensure that the survey design and initial nonresponse
in the 1984 survey is also accounted for. As the application of weights is a key
factor in the subsequent analysis, the survey weight is introduced here. Although there is
some disagreement about the quality and general applicability of survey weights, it is
now generally accepted in the statistical community that the sampling design and nonresponse
for a survey should be accounted for in order to obtain estimates that reference
the population. As the ALS was not a simple random sample 115 , then it is important that
the survey weights are applied.
There is a selection/response weight provided with the data 116 , which weights the 1984
data back the population: persons aged 15-24 on 1 September 1984, registered with the
Commonwealth Employment Service offices throughout Australia who were unemployed
and seeking full-time work for three months or more at the time of selection, 30 June
1984 117 . To construct the weight for non-response and selection provided with the data,
administrative data was used to weight back to the population. The weight is complex,
adjusting for unequal probability of selection, non-response using administrative data on
specific categories, and benchmarking adjustment to known totals 118 to reduce the
standard errors and produce estimates comparable with other sources. Foreshadowing
115 It was a stratified cluster sample. Those interested in the sample design details should refer to
Kronenburg et al. (1985). Non-computerisation led to a number of issues in the ‘list’ sample which affected
the sample design, as the records that made up the sample frame were in fact paper card records stored at
each CES office. The key problem was double-counting and multiple registrations at several CES.
Stratification was also not always straightforward – for the Northern Territory, in Alice Springs almost all
the unemployed youths were Aboriginal (716 of 886), a much different proportion to all other locations and
so only those in Darwin were chosen to represent the Northern Territory (Kronenburg et al. (1985): 7).
116 The variable in 1984 is named ‘Weight1’.
117 In fact, the sample was of 2 stages – (1) selection of CES offices based on the persons aged 15-24 on 1
September 1984, registered with the CES offices throughout Australia who were unemployed and seeking
full-time work for three months or more at 31 March. (2) samples of 50 persons [persons aged 15-24 on 1
September 1984, registered with the CES offices throughout Australia who were unemployed and seeking
full-time work for three months or more] selected from each office on 30 June 1984. The March and June
numbers in scope of the survey were different, leading to differing selection probabilities. (Mcrae et al.
(1985): 23).
118 The benchmark data came from CES population counts for each age*sex*duration of registration
category within the geographic selection strata (Mcrae et al. (1985: 24).