Dear experts,

I am using RooFit to make a weighted binned likelihood fitter with Extended() and SumW2Error() options. According to the manual, minNll() is not usable while SumW2Error() is enabled.

I also tried to do a likelihood scan on one of the fit variables, and it turned out the likelihood distribution didn’t make sense as well.

Therefore, I am wondering if there any other alternative way to represent the goodness of a fit for this case? Calculating chi^2 manually by using the fit result is one way, but if RooFit provides other number instead of nll for this case, such that we can calculate significance level or upper limit for a specific PDF?

Thank you in advance.