"Ron�n Conroy" <[email protected]> wrote:
-regress- is a lot faster than t-test, and the output is easier to read,
IMO. The coefficient and its confidence interval represent
the difference in means and its CI.
While I agree that regress is faster and often preferred to t-tests, one
should be aware that regress will assume equal variances for the two
groups identified by the dummy variable. That assumption may or may not
be what you want.
-regress- has a -robust- option to handle unequal variances. However, it is
a valid point that (unlike -ttest-) -regress- does not use a
Sattertwhaite-corrected degrees of freedom formula, so there is the danger
that confidence intervals will be over-conservative at small sample sizes.
