Re: [office-formula] ZTEST

From
Rtefan @ikolaus
Date
2007-02-09T12:29:50+00:00
ID
Thread
Re: [office-formula] ZTEST
On Friday 09 February 2007 12:56:09 Stefan Nikolaus(UNTRUSTED, sender is 
<srs0=vgmu=hr=lists.oasis-open.org=office-formula-return-280-stefan.nikolaus=>) 
wrote:
> gauss() is the method returning the value for GAUSS (what a surprise ;-) ).
> And that is defined as NORMDIST(x)-0.5. NORMDIST(x) returns the value of
> the normal distribution pdf (!) at position x. Is that what you call the
> p-value? I think not. You want the value of the cdf! Otherwise, it makes no
> sense at all (AFAICT).

Whoops. I got this wrong: the default of NORMDIST() is to return the cdf. That 
means
                PushDouble(0.5 - gauss((mue-x)/sqrt(sigma/rValCount)));
could be written as
                PushDouble(1.0 - NORMDIST((mue-x)/sqrt(sigma/rValCount)));
, which is the one-tailed test and which fails for a negative argument of 
NORMDIST().

Regards,
Stefan

-- 
Stefan Nikolaus
humba, humba, tätärää, tätärää, tätäräää ;-)