chi square PDF fitting

Hello,

similar to how I can use fit function with fittype = 'exp1' to find the best f(x)=a*exp(b*x) to match my distribution,

how can I find the best chi square PDF to match my distribution?

By chi square pdf I mean as it defined in: Y = chi2pdf(X,V).

If in exp case I could have the [a,b] that would give me the best fit, here I'm searching for the best V that would give me the best fit.

Thanks!

Answer 1

[Jeff Miller]

Cupid will fit the chi-square distribution. For example, if you have a vector of scores, x, from the distribution to be fit, you can get a maximum-likelihood fit with:

mydist = ChiSq(round(mean(x));  % A good starting value.
mydist.EstML(x)  % Will adjust V up or down to improve max-likelihood fit.