> -----Original Message-----
> From: Siyam,AA (pgr) [mailto:A.A.Siyam@lse.ac.uk]
> Sent: Wednesday, June 12, 2002 1:07 PM
> To: statalist@hsphsun2.harvard.edu
> Subject: st: RE: RE: Bootstrapping and t-tests
>
>
> Sorry that was a typing error of mine - still the error
> message I get tells me:
>
> bs "ttest prert=postrt" "_b[prert] _b[postrt]", reps(50) n(10)
> command: ttest prert=postrt
> statistics: _b[prert] _b[postrt]
> error in statistic: _b[prert]
> r(198);
>
The t-test command does not return results in _b[varname]. In the
syntax you are using, you should type:
. bs "ttest prert=postrt" "r(mu_1) r(mu_2)", reps(50) n(10)
You can find out how a command returns results by typing -return list-
(for r-class commands) or -estimates list- (for estimation commands).
I imagine you probably want to pick up something like "r(p)" (the
p=level of the test), or "r(t)", the t-ratio for the ttest. As it
stands, you are just getting the two bootstrapped mean estimates.
--Nick Winter
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