1. The corr2data command is handy if, say, there is a published analysis
that includes the means, correlations and sds, and you want to replicate or
modify the work (e.g. add or drop variables). I do this in some classroom
exercises. At the same time, you have to remember that these are not the
original data, and you are very limited in what you can do, e.g. you can't
analyze subsets of the data, compute interaction terms, etc. All you can
do is basic correlational and regression analysis with no modifications of
the data (correct?). If I had to invent a term, I would call a data set
created by corr2data a pseudo-replication of the original data, but is
there a standard term already in use?
2. Is there any reason the N for the corr2data command has to be the same
as in the original data? I did a little experiment where I created a data
set with 200,000 cases and ran a regression. I then created a 2nd data set
with N = 200 and ran a regression specifying fw=1000. Results were
virtually identical. Anyway, if the original data set was monstrous, this
might be a way of saving disk space and computing time.
