Skip to content

Implementation of ST prescription for QCDscale uncertainty

Nicolas Postiau requested to merge npostiau/shears:systematic_uncertainties into master

Stewart-Tackman prescription for QCDscale. It's performed bin-by-bin, in mT. Still a preliminary version; it could be updated after discussions (need to check if the method makes sense!). Caution: does not work for signal (it changes the total normalization, we don't want that for the signal). Should be fine for all MC-based backgrounds. As you probably know, this prescription affects only exclusive jet categories, i.e. only the eq0jets in our case. The other distributions won't be changed.

Technical points:

  • Now the QCDscale uncertainty has also to be launched in only 1 job. It's a bit slower, but you're not supposed to compute syst uncertainties everyday either.
  • I had to add a whole set of "nominal" histos to the root file, only when running on QCDscale. It does not change anything (just don't look at them) but it was needed to apply the prescription.

Merge request reports