Dear all
I have a question concerning the fit statistics. When you print the fit statistics, there is one that is “Prob”…what does that mean? Is that the probability that the function ( gaus, expo, landau, etc… ) fits the histogram?
Sorry if this is a bad question.
Lizardo
Hi,
“Prob” is the p-value of the chi2 goodness of fit test. It corresponds to the probability to obtain chi2 values larger than the one obtained in the fit.
Lower p-value will indicate a less likely fit results. The test hypothesis is that the function is in agreement with the data, and it can be rejected when the p-value is smaller to some significance level (for example few %).
You can find more information in any statistics books or even on the wikipedia under the chi2 goodness of fit test
Best Regards
Lorenzo
Thank you very much for your help.