Re: st: functions for computing prob

[Gary Longton <glongton@fhcrc.org>]

It appears that I was mistaken about -tprob()-, that it does exist and appear to 
work, though undocumented and apparently obsolete.  It looks to be the 2-tailed 
version of -ttail()-

. di tprob(30,1.8)
.08192507

. di ttail(30,1.8)
.04096253

- GL


Gary Longton wrote:

> Lei Xuan wrote:
>
> > I am computing probabilities for t-test and z-test.
> > I want to know if the functions -tprob- and -normprob- are out-of-date
> > since no help files explain these functions. Are -ttail(n,t)- and 
> > -normal(z)
> >
> > right functions to compute probs?
>
> see -help density functions-
> or -help functions-
>
> Yes, the cumulative normal density function, normprob(), still works but 
> is out of date, no longer documented, and has been replaced by 
> normal().  Am not sure whether tprob() ever existed? - doesn't seem to 
> work and is not documented in any case.  ttail(n,t) is documented under 
> help for functions.
>
> - Gary
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