1 Unfolding Study Closure test on SHERPA 08/16/12

2 RooUnfold Using the RooUnfold In this study we make response matrix from MADGRAPH MC and use it to unfold the SHERPA sample We re-compute the uncertainty with equation from Darko. The unfolding methods are  Svd  Bin by Bin → re-compute uncertainty.  **Bayes method cannot unfold.

3 0.5|Y z -Y jet | with Svd Different ktermOnly kterm =2 The lower the kterm, the smaller the uncertainty. Except the last 3 bins that uncertainty would be smaller to one point and do not change. Changing the kterm only change the uncertainty but not central value.

4 0.5|Y z -Y jet | with Bin by Bin Bin by Bin and Svd kterm =2 Bin by Bin Comparison between Bin by bin and Svd shows that central values do not change with unfolding method but only uncertainty changes (bin by bin gives a little smaller uncertainty). The uncertainty calculation from Darko can use to lower the uncertainty of bin by bin method.

5 Keng's Comments 1. Bayes method cannot be done for the closure test (error in root). 2. These result confirm that changing method and kterm only change uncertainty but not central values. 3. What method do we want to put in the paper? Bin by bin with Darko's uncertainty?