MATLAB Central Newsreader - Chi-test distribution

Chi-test distribution

Erez Livneh — Thu, 01 Jan 2009 14:48:02 -0500

Hi Matlabers,

How do I get one-tailed probability of the Chi-test distribution?
I require the same function as the CHIDIST function in Excel.

Thanks and Happy New Year!
Erez

Re: Chi-test distribution

John D'Errico — Thu, 01 Jan 2009 16:11:02 -0500

"Erez Livneh" <erezliv@gmail.com> wrote in message <gjil32$n92$1@fred.mathworks.com>...
> Hi Matlabers,
>
> How do I get one-tailed probability of the Chi-test distribution?
> I require the same function as the CHIDIST function in Excel.
>
> Thanks and Happy New Year!
> Erez

I've never heard of the Chi-test distribution.
Perhaps you are thinking of this instead?

help chi2inv
CHI2INV Inverse of the chi-square cumulative distribution function (cdf).
    X = CHI2INV(P,V) returns the inverse of the chi-square cdf with V
    degrees of freedom at the values in P. The chi-square cdf with V
    degrees of freedom, is the gamma cdf with parameters V/2 and 2.

John

Re: Chi-test distribution

Frederic — Tue, 14 Jun 2011 17:00:21 -0400

> "Erez Livneh" <erezliv@gmail.com> wrote in message <gjil32$n92$1@fred.mathworks.com>...
> > Hi Matlabers,
> >
> > How do I get one-tailed probability of the Chi-test distribution?
> > I require the same function as the CHIDIST function in Excel.
> >
> > Thanks and Happy New Year!
> > Erez

Erez, the Matlab formula corresponding to excel CHIDIST function is:

1-chi2cdf(x,df)
where x is the calculated Chi Square and df the degree of freedom

Frederic

PS: the response is a bit late, but it took me a while to find this out. Now should be fast to find for all!!