From roxburg@kih.net  Sat Oct  5 21:27:49 2002
From: roxburg@kih.net (roxburg@kih.net)
Date: Sat, 5 Oct 2002 22:27:49 +0200 (MET DST)
Subject: Welch versus Satterthwaith (PR#2111)
Message-ID: <200210052027.WAA01389@pubhealth.ku.dk>

This is not a bug report but didn't see another way to ask a question.

For the approximate t-test assuming unequal variances, the R docs cite
Welch's method for the df of the approximating distribution.
I have several methods books, and they all uses Satterthwaite's method.
Why does R use Welch's method where can I learn about Welch's method?

Sincerely,
David Allen


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Welch versus Satterthwaith (PR#2111)
roxburg@kih.net