Evaluation of the Australian Wage Subsidy Special Youth ...

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5.6.1 Survey design and non-response effects on modelling
Mcrae et al. (1985) found that the strong differential response effect for movers and nonmovers
affected labour force variables measured in the 1984 survey. They pointed out
that models and estimates of such variables might be biased by the non-response, unless
the weights were applied. Movers, who had much lower chance of interview, were more
likely than non-movers to be older than 20, married and in employment 121 , and had
briefer CES registration. The definition of the SYETP treatment group relies on 1984
survey data. The eligibility criteria for SYETP, and the other evidence 122 that they were
more likely to be teenagers, hints that SYETP participants would more commonly have
been non-movers, and have had a higher response rate. In light of this, the SYETP
participation model is first examined, by exploring the effects of the survey weights. The
aim is to study the influence of non-response, and so check whether the mobility, age,
gender, duration of registration and state of registration were related to the variable of
interest here, SYETP participation.
5.6.1.1 Analytical selection
Before continuing, the analytical selection from the full data is examined. Recall the
limits of the sample: the exclusion from those interviewed in 1984 of those who were
over 25 years at the interview date, those in full-time education, or for whom responses
were missing in 1984, 1985 or 1986 (Richardson (1998): 5). For the purposes of
evaluation analysis of SYETP, only those who were aged less than 25 and not in fulltime
education in the 1984 survey interview can be of interest due to the eligibility restrictions
for SYETP.
These are discarded at different stages of the analysis however. Age was observed in the
administrative data, and is accounted for in the non-response weight and so it is
121 Movers were also less likely to be unemployed, but had the same proportions not in the labour force as
non-movers.
122 See Chapter 2, for example the results of Hoy and Lampe (1982) covered in Section 2.2.6.2.