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arXiv · 0812.0922

PDE-Foam - a probability-density estimation method using self-adapting phase-space binning

Dominik Dannheim·Tancredi Carli·Karl-Johan Grahn·Peter Speckmayer·Alexander Voigt
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Abstract

Probability Density Estimation (PDE) is a multivariate discrimination technique based on sampling signal and background densities defined by event samples from data or Monte-Carlo (MC) simulations in a multi-dimensional phase space. In this paper, we present a modification of the PDE method that uses a self-adapting binning method to divide the multi-dimensional phase space in a finite number of hyper-rectangles (cells). The binning algorithm adjusts the size and position of a predefined number of cells inside the multi-dimensional phase space, minimising the variance of the signal and background densities inside the cells. The implementation of the binning algorithm PDE-Foam is based on the MC event-generation package Foam. We present performance results for representative examples (toy models) and discuss the dependence of the obtained results on the choice of parameters. The new PDE-Foam shows improved classification capability for small training samples and reduced classification time compared to the original PDE method based on range searching.

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Dominik Dannheim, Tancredi Carli, Karl-Johan Grahn, Peter Speckmayer, Alexander Voigt. 2009-07-22. PDE-Foam - a probability-density estimation method using self-adapting phase-space binning. https://doi.org/10.1016/j.nima.2009.05.028

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