Modelling Systematic Uncertainties

Hi all, please I need some help! I would like to see a distribution of MCEventWeight_MC14, but I find only something wrong like this in the picture?

I do not know exactly if this error means I’m missing something in the code or some other parameter somewhere?

It seems that you have 666 events and for (almost?) all of them: MCEventWeight_MC14 = 1.0


Could you elaborate a bit on what it is we are seeing? What is this variable MCEventWeight_MC14, where does it come from and how are you plotting it?

It seems indeed as @Wile_E_Coyote says, all the events are generated with the same weight.



@kialbert , My goal is to produce the EasyTree distribution for MCEventWeights_MC14 variable in the output folders. so I add some lines of code to my file.cxx and I run the code over this variable.

here are the lines of code that I added:

bool isVJetsFromSherpa = ((364114 <= m_eventInfo->mcChannelNumber() && m_eventInfo->mcChannelNumber() <= 364197) || (364100 <= m_eventInfo->mcChannelNumber() && m_eventInfo->mcChannelNumber() <= 364113));
m_etree->SetBranchAndValue(“MCEventWeight_CT14”, (m_eventInfo->mcChannelNumber() == 410472) ? Props::MCEventWeightSys.get(m_eventInfo).at(10) : (isVJetsFromSherpa ? Props::MCEventWeightSys.get(m_eventInfo).at(114) : 1.0), 1.0);