Speakers
Dr
Alberto Ribon
(CERN)Dr
Andreas Pfeiffer
(CERN)Dr
Barbara Mascialino
(INFN Genova)Dr
Maria Grazia Pia
(INFN GENOVA)Dr
Paolo Viarengo
(IST Genova)
Description
Statistical methods play a significant role throughout the life-cycle of high energy
physics experiments. Only a few basic tools for statistical analysis were available
in the public domain FORTRAN libraries for high energy physics. Nowadays the
situation is hardly unchanged even among the libraries of the new generation.
The present project in progress develops an object-oriented software toolkit for
statistical data analysis. The Goodness-of-Fit (GoF) Statistical Comparison component
of the toolkit provides algorithms for the comparison of data distributions in a
variety of use cases typical of physics experiments. The GoF Statistical Toolkit is
an easy to use, up-to-date and versatile tool for data comparison in physics
analysis. It is the first statistical software system providing such a variety of
sophisticated and powerful algorithms in high energy physics. The component-based
design uses object-oriented techniques together with generic programming. The
adoption of AIDA for the user layer decouples the usage of the GoF Toolkit from any
concrete analysis system the user may have adopted in his/her analysis. A layer for
user input from ROOT objects has been easily added recently, thanks to the
component-based architecture. The system contains a variety of two-sample GoF tests,
from chi-squared to tests based on the maximum distance between the two empirical
distribution functions (Kolmogorov-Smirnov, Kuiper, Goodman), to tests based on the
weighted quadratic distance between the two empirical distribution functions
(Cramer-von Mises, Anderson-Darling).
Thanks to its flexible design the GoF Statistical Toolkit has been recently extended,
implementing other less known GoF tests (weighted formulations of Kolmogorov-Smirnov
and Cramer-von Mises tests, Watson and Tiku tests). Nowadays the GoF Statistical
Toolkit represents the most complete system available for two-sample GoF hypothesis
testing, not only in the domain of physics, but even in professional statistics
analysis.
The toolkit is open-source and can be downloaded from the web together with user and
software process documentation. It is also distributed together with the LCG
Mathematical Libraries.
We present the recent improvements and extensions of the GoF Statistical Toolkit; we
describe the architecture of the extended system, the new statistics methods
implemented, some results of its application, and an outlook towards future developments.
Primary authors
Dr
Alberto Ribon
(CERN)
Dr
Andreas Pfeiffer
(CERN)
Dr
Barbara Mascialino
(INFN Genova)
Dr
Maria Grazia Pia
(INFN GENOVA)
Dr
Paolo Viarengo
(IST Genova)
