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arXiv · 0912.2276

Fitting Parton Distribution Data with Multiplicative Normalization Uncertainties

The NNPDF Collaboration·Richard D. Ball·Luigi Del Debbio·Stefano Forte·Alberto Guffanti·Jose I. Latorre·Juan Rojo·Maria Ubiali
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Abstract

We consider the generic problem of performing a global fit to many independent data sets each with a different overall multiplicative normalization uncertainty. We show that the methods in common use to treat multiplicative uncertainties lead to systematic biases. We develop a method which is unbiased, based on a self--consistent iterative procedure. We demonstrate the use of this method by applying it to the determination of parton distribution functions with the NNPDF methodology, which uses a Monte Carlo method for uncertainty estimation.

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The NNPDF Collaboration, Richard D. Ball, Luigi Del Debbio, Stefano Forte, Alberto Guffanti, Jose I. Latorre, Juan Rojo, Maria Ubiali. 2010-06-01. Fitting Parton Distribution Data with Multiplicative Normalization Uncertainties. https://doi.org/10.1007/jhep05(2010)075

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