The -metaparm- module of the -parmest- package allows the user to calculate unequal- or equal-variance t-tests on differences between group means, saving the results in output datasets (or resultssets) as differences with confidence limits and P-values. The latest Stata 9 version of the -parmest- package can be downloaded from SSC using the Stata command
ssc install parmest, replace
I hope this helps.
Best wishes
Roger
Roger Newson
Lecturer in Medical Statistics
Respiratory Epidemiology and Public Health Group
National Heart and Lung Institute
Imperial College London
Royal Brompton campus
Room 33, Emmanuel Kaye Building
1B Manresa Road
London SW3 6LR
UNITED KINGDOM
Tel: +44 (0)20 7352 8121 ext 3381
Fax: +44 (0)20 7351 8322
Email: r.newson@imperial.ac.uk
www.imperial.ac.uk/nhli/r.newson/
Opinions expressed are those of the author, not of the institution.
-----Original Message-----
From: owner-statalist@hsphsun2.harvard.edu [mailto:owner-statalist@hsphsun2.harvard.edu] On Behalf Of Claude Francoeur
Sent: 07 January 2007 18:44
To: statalist@hsphsun2.harvard.edu
Subject: R�p. : st: t test between groups
Thanks to Herv� and Nick for the answers. I am still looking for a way to
have Stata calculate "t tests" on total sample SD (see "Testing group
means"). Anyone know how to do this?
Claude
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* For searches and help try:
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