st: Corr2data questions

[Richard Williams <Richard.A.Williams.5@nd.edu>]

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.


-------------------------------------------
Richard Williams, Associate Professor
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