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st: choosing the seed for random number generation


From   "Stephen P. Jenkins" <stephenj@essex.ac.uk>
To   statalist@hsphsun2.harvard.edu
Subject   st: choosing the seed for random number generation
Date   Thu, 31 Oct 2002 18:40:53 +0000 (GMT Standard Time)

The default seed for Stata's (pseudo-)random number generator in 
the function -uniform()- is 123456789.  Are there any guidelines about 
for choosing the seed value in applications? And any benefits from 
choosing something other than the default? 
[I know that once you've set the seed to a particular in an 
application, you stick to it, in order to maintain reproducibility of 
results. But this is a Qn about the criteria used for choosing the seed 
in the first place.]

So far, the most explicit guidelines I have found (via Google) are:
http://www.npac.syr.edu/projects/random/brief.html
"2.Use seeds that are "somewhat random", i.e. have a good mixture of 
bits. For example 2731774 and 10293082 are "safer" than 1 or 4096 (or 
some other power of two). ..."
[Why powers of 2 are relevant is clear from the formulae in the Stata
User Guide [U] page 118.]


Stephen
----------------------
Professor Stephen P. Jenkins <stephenj@essex.ac.uk>
Institute for Social and Economic Research (ISER)
University of Essex, Colchester, CO4 3SQ, UK
Tel: +44 (0)1206 873374. Fax: +44 (0)1206 873151.
http://www.iser.essex.ac.uk

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