RooFit: Simultaneous fit

Roofit and RooStats
1

I made xml files for fitting as MyUserAnalysis.tar.gz (1.66 KB) .
With these xml files, I’d like to execute simultaneous fit for three parameters:
mu_mu_Sig, mu_eff_B, mu_eff_C

I’d like to implement fitting with data
in channel “B_cuts”: mu_mu_Sig * mu_eff_B
in channel “C_cuts”: mu_mu_Sig * mu_eff_C
in channel “D_cuts”: mu_mu_Sigmu_eff_Bmu_eff_C

I prepared test data samples for each region:
in channel “B_cuts”: 20 events
in channel “C_cuts”: 50 events
in channel “D_cuts”: 100 events

After I made workspace MyUserAnalysis.root (6.44 KB),
I executed the fitting.

However, after the fitting, final value become like this:
mu_mu_Sig = 2.3
mu_eff_B = 2.4
mu_eff_C = 6
In any channels, these values don’t show agreement.
Are there any mistake in fitting implementation ?

The log file is herefit.log.tar.gz (2.96 KB).

Thank you.

2

Hi,

Can you please attach also the final workspace you are getting from the HistFactory and possibly a macro doing the fitting, so it I can reproduce your problem and try to understand it better ?

Lorenzo

3

Hi,

Sorry, I attached wrong file in previous post.
Here is the result of hist2workspace.
ABCD_combined_NormalMeasurement_model.root (50.8 KB)

To tell the truth, I didn’t write the fitting macro.
I use HistFitter to run fitting.
histfitter.web.cern.ch/histfitter/
GenerateFitAndPlot function in this source file is used for fitting.
Utils.cxx (112 KB)

Thanks,
Yuto

4

Hi,

I found this is because I made mistake to make dummy BG histogram for each region with HistFitter.
The problem was solved.

Thank you.

Yuto