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Bias-Free Estimation in Multicomponent Maximum Likelihood Fits with Component-Dependent Templates

P. Catastini·G. Punzi
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Abstract

The possibility of strong biases in a multicomponent Maximum Likelihood fits with component-dependent templates has been demonstrated in some toy problems. We discuss here in detail a problem of practical interest, particle identification based on time-of-flight or dE/dx information. We show that large biases can occur in estimating particle fractions in a sample if differences between the momentum spectra of particles are ignored, and we present a more robust fit technique, allowing bias-free estimation even when the particle spectra in the sample are unknown.

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P. Catastini, G. Punzi. 2006-05-16. Bias-Free Estimation in Multicomponent Maximum Likelihood Fits with Component-Dependent Templates. https://doi.org/10.1142/9781860948985_0014

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