st: -ttest- (repost)

[Constantine Daskalakis <constantine.daskalakis@mail.tju.edu>]

I am not sure whether my previous message on -ttest- got posted or not (did 
not receive any replies on what seemed a simple comment)...

It seems that the default -ttest- (equal variances assumption) and the 
-ttest- with the option 'unequal' give the same test statistic. It appears 
that the first one is in error (ie, does not use the pooled estimator). Can 
someone confirm?

(the -ttesti- seems to be fine)

Thanks,
cd


________________________________________________________________

Constantine Daskalakis, ScD
Assistant Professor,
Biostatistics Section, Thomas Jefferson University,
125 S. 9th St. #402, Philadelphia, PA 19107
   Tel: 215-955-5695
   Fax: 215-503-3804
   Email: constantine.daskalakis@mail.tju.edu
   Webpage: http://www.kcc.tju.edu/Science/SharedFacilities/Biostatistics

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