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Re: st: Problem with seed and bootstrap


From   Richard Williams <Richard.A.Williams.5@ND.edu>
To   statalist@hsphsun2.harvard.edu
Subject   Re: st: Problem with seed and bootstrap
Date   Mon, 19 Sep 2005 11:45:52 -0500

At 10:53 AM 9/19/2005, William Gould, Stata wrote:

Alejandro's problem may well be that the formula he is bootstrapping is not
determinant and, if so, that should bother him.  At this point, all we really
know is that -stable- solved the reproducibility problem.  There is one thing,
however, that I can guarantee:  there is a program bug or a substantive error,
and -stable- is covering it up.
I think what is most troubling about -unstable- is that its results can't be reproduced; you can run the exact same problem twice and get different sort orders. Further, -set seed- has no effect on this. That goes counter to the idea that you should be able to exactly reproduce results; and it also seems odd that the exact same commands produce different outcomes. I can understand not knowing in advance how a sort will turn out, but having done it once I'm surprised it doesn't come out the same way the next time. If -unstable- produced reproducible outcomes i think people would feel more comfortable with it.


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Richard Williams, Notre Dame Dept of Sociology
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