Propagate normalization uncertainties using VisualizeError for RooSimultaneousPdf

[Jiayi_Chen]

Hi,

We are trying to make post-fit plots, displaying the uncertainty from the PDF. However, the error band is much smaller than expected comparing to pre-fit uncertainty. We found some ticket reporting trouble propagating normalization uncertainty (ticket name: [Normalization uncertainties in VisualizeError])

And we found the follow up discussion about this bug not fully fixed by adding Normalization() for RooSimultaneousPdf: ROOT-9971

Here are the plotOn cmds we have:
pdf->plotOn(xplot,RooFit::Name(“sysErrorPdf”),RooFit::Slice(*channelCat,channel->GetName()),RooFit::ProjWData(*channelCat,*asimov),RooFit::LineColor(kBlack),RooFit::LineWidth(1),RooFit::LineStyle(1),RooFit::VisualizeError(*rnomStat),RooFit::FillStyle(3325),RooFit::FillColor(kBlack),RooFit::Normalization(1.0, RooAbsReal::RelativeExpected));

Using Normalization() the error band disappeared.

We use an older root version: 6.10/06

We wonder if this issue persists? Is there a workaround about it in the old root version? Many thanks in advance.

Best,
Jiayi

[moneta]

Hi,
I think the problem still exists as reported in ROOT-9971 when the plots are projections of the RooSimultaneous. I am not sure if a workaround exists especially in the old ROOT version. Maybe @jonas knows more

Best,

Lorenzo