Roofit and TTree Weight

I have three data samples (signal1, signal2, background) with different integrated luminosities, and I want to merge them to the same int. luminosity, to fit the resulting TTree (converted in a RooDataSet) with RooFit.
Does RooFit recognise the TTree::SetWeight() method, and use it to compute the right errors to associate to each entry?


RooFit does not work with the TTree::SetWeight() feature (I didn’t even know it existed!). You can easily make weighted datasets in RooFit though
by adding a weight variable to the dataset and requesting that it be interpreted as event weight by adding a Weight(“wgt”) to the RooDataSet ctor where “wgt” is the name of the variable you want interpreted as event weight.