Evaluation of the Australian Wage Subsidy Special Youth ...

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However, the Richardson (1998) examination of non-response was less developed than
the earlier SYETP analyses where non-response was considered. In common with all the
SYETP analyses, survey data was used. Stretton (1984) and Baker (1984) modelled nonresponse
in their observational data and found non-response was a potential problem. As
both of these had the administrative sample frame to identify some variables for
modelling non-response to the survey, they were at an advantage. Richardson (1998)
could not benefit from the administrative sample frame as this was not available with the
survey data deposited, and this precluded this type of analysis. However it was possible
to choose to use the non-response weights provided with the data, which had been
developed from the non-response analysis for the first survey using the administrative
data. Further, the panel of data used had 3 subsequent surveys, to which non-response 59
could be modelled from the first survey.
In common with the earlier analyses, no treatment for non-response was applied. In the
case of Richardson (1998) this was in line with the conclusions maintained from the
analysis of non-response. For earlier evaluations by Stretton (1984) and Baker (1984) this
was in spite of the conclusions about the existence of a potential non-response problem
for estimates as a result of useful models of survey non-response from the administrative
data sample. For Rao and Jones (1986), which used data from Baker (1984) but with
additional survey data, ignoring non-response was in conflict with the Baker (1984)
analysis, and the aggravation of non-response problems due to further attrition to the later
survey was also ignored. In review it is likely that the choice of models potentially
available with computing resources at the time limited modelling in these earlier analyses
of SYETP. A choice had to be made as to what was the most important modelling
consideration, given the computational capabilities of the time. As a result, non-response
was not further accounted for. This is an adequate modelling assumption, but further
invokes the assumption that the non-response was ignorable for their modelling. In
Stretton (1984) and Baker (1984), the examination of non-response indicated this was not
generally tenable. This issue is dealt with in the study of non-response that follows.
59 Usually termed attrition in this case.