Spectator variables in correlation matrix

TMVA
1

Hi all, is there a way to insert the spectator variables inside the correlation matrix for signal and background?Thanks in advance!

2

@moneta can help I guess.

3

Hi,

Do you mean adding the spectator variables for the computation of the overall correlation matrix that is performed at the beginning in TMVA when building the internal data set ?
There it is not possible to use the spectator, the correlation is computed using only the standard variables.
You can however compute yourself the correlation/.covariance matrix with some code, either from the TNVA DataSet, see for example:
https://root.cern/doc/master/DataSetFactory_8cxx_source.html#l00579
Or if you have the input data in an array you can also use the TPrincipal class and TPrincipal::GetCovarianceMatrix.

Cheers

Lorenzo

4

Thanks a lot for the response! The fastest way I found so far is plotting the correlation plots from the TrainTree using the className flag to select Signal and Background.