Getting fitted templates normalisations from TFractionFitter

ROOT
1

Dear All,

      I am trying to fit the normalisation of two mc templates using TFractionFitter.
      Please find attached a tar ball with an example of what I've been doing.
      (The root file was produced using 5.34.07a).

      From step1 and step2 it would seem like TFractionFitter is doing a good job.
      Now, by using the output from TFractionFitter::GetResult(parameter #), 
      I was expecting to be able to describe the data as :
           data = parameter_0 * mc_1 + parameter_1 * mc_2
      but from step3 it would seem like I've misunderstood the meaning of these parameters ...

      Would anybody know how to get the scale factors from the fitting ?
         i.e.   data = factor_1 * mc_1 + factor_2 * mc_2

      Thanks,
             Nicolas

ForROOTalk.tar.gz (23.8 KB)

2

Just in case some one ends up here.

The correct normalization is

Data = [frac1data.Integral()/mc1.Integral()] + [frac2data.Integral()/mc2.Integral()]

Also please go through this discussion. TFractionFitter Template Distortion

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