How is the BDT separation value calculated

TMVA
1

Hey all, I’m fairly new to TMVA so sorry if this is a basic question, I could not find the answer for this anywhere else.
I’m working with BDT and I am struggling to understand the output. At the end of the output log file, I am being told a Separation value and the corresponding significance. How is this separation value calculated. Is this just the value with the highest purity?
Thanks!

EDIT: Or is it just the value with the highest significance given by mvaeffs.C?

2

Hi,
I am not sure exactly on which output and separation value you are referring to. Can you please elaborate more, quoting exactly the information that the algorithm provides to you

Thank you

Lorenzo

3

Hi,

May I know do you make it?

4

Hi,

The definitions used for TMVA for significance and separation can be found in the TMVA User’s Manual (https://root.cern/download/doc/tmva/TMVAUsersGuide.pdf) page 25.

Cheers,
Kim