Evaluation of the Australian Wage Subsidy Special Youth ...

95
taken by a previous researcher and then improve on the data or methodology in some way
or another…”.
Dewald et al. (1986) provide evidence of the value of the application of the replication
standard. They point out that the confirmation of research findings through replication by
other researchers is an essential component of scientific methodology. To examine the
role of replication in empirical economic research they took one year's worth of articles
from The Journal of Money, Credit and Banking and attempted replication of all the
articles. Extensive efforts were reported but also largely failed attempts to replicate the
findings as they were reported. They often found that replication was impossible based on
the information in the articles, and also subject to ambiguities, errors and oversights in
the reporting. They emphasized that replication is an essential element in the evaluation
and unification of the results for a group of studies.
3.2 Methods: The Heckman selection model
The specification to be replicated is the bivariate probit of employment, where the
selection equation modelled is that of selection into SYETP. The analysis based on the
‘1986 data’ is attempted here, and the results as shown in Richardson (1998) Tables 4 and
5 are replicated.
3.2.1 Self-selection and the evaluation of programmes
Evaluating the benefits of a social programme is one of the major uses of self-selection
models. There are many variations of the self-selection model depending on the problem
the model is applied to solve. The terminology is that of the experiment, where the
programme is the treatment being evaluated. The individuals who participate in the
programme are the treatment group and others not participating are in the comparison
group. In the case of the SYETP, it is assumed that the programme administrator
essentially makes the assignment of individuals to the treatment groups, but the process is
jointly determined with the employers and the participant. Selection onto the programme
could have led to systematic differences between those who went on the SYETP and