Evaluation of the Australian Wage Subsidy Special Youth ...

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suitability of the underlying assumption of the bivariate normal distribution for the errors
in the participation and employment equations.
3.3 Data and variables used for estimation
The first stage of the replication, whereby the variables used in the analysis are reconstructed,
is made easier by access to the final data set used as the basis for the
Richardson (1998) analysis. 61 It was pointed out by Dewald et al. (1986) that access to
the author’s data, with the variables in the final form used for the analysis, is an
invaluable assistance in replication, but observed that this was an unusual occurrence.
They attributed this to angst held by authors as they “…may interpret the very act of
replication as a challenge to their professional competence and integrity” (Dewald et al.
(1986): 601). In light of this, the access granted by the author James Richardson is
strongly appreciated.
As a result of access to the transformed data, replicating the exact construction of the
variables is simplified. This would normally be an exacting task, as the construction of
complex variables such as those derived from the work history is extremely difficult to
repeat without the exact details of construction, and even the exact syntax coding. Any
variation in construction would make replication far more difficult, and overcoming this
hurdle also allows interpretation of the replication results to be more precise. It should
not be overlooked that this stage of a replication would normally be most difficult. The
variables are described in the data appendix.
A brief introduction to the data is informative. The Australian Longitudinal Survey List
Sample (Mcrae et al. 1984-1987) is used. This was a sample drawn from an
administrative sample frame. The ALS list sample was a nationally representative sample
of Australian youths aged 15-24 who had been registered as unemployed with the
Commonwealth Employment Service for at least 3 months in June 1984. The 1984
survey took place with interviews between September 1984 and November 1984. The
survey was repeated in each of the later years 1985, 1986 and 1987, following up where
61 The data were transformed from the ALS original SPSS files in extensive STATA processing by
Lorraine Dearden, Alex Heath, Henry Overman, and James Richardson.