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From: Brian Borchers <borchers.brian@gmail.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Problem with chi2pdf command
Date: Tue, 20 Oct 2009 07:09:59 -0700 (PDT)
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On Oct 20, 7:56 am, Mehdi <zeido...@gmail.com> wrote:
> Hello everyone:
> I am using the command below to find the probability of chi-square
> larger than 0.0052 with 1 degree of freedom: chi2pdf(0.0052,1)
> for this I am getting a probability of 5.5164 which is larger than 1
> (the probability should vary between 0 and 1). Any comment on this is
> much appreciated.
>
> Yours,
> Mehdi

You want the CDF, not the pdf, of the Chi^2 distribution.  Use chi2cdf
instead.