A cross-validation check in the covariance analysis of isospin sensitive observables from heavy ion collisions

Abstract

Partial correlation coefficients measure the strength and direction of the linear relationship between two random variables, while controlling the effect of one or more other variables. The usefulness of partial correlation coefficients in heavy ion collisions data analysis is discussed in this paper. Detailed calculations based on the results concerning (complete) correlation coefficients between the so called input parameters in transport models and isospin sensitive observables that allow for obtaining information on the symmetry energy are presented. It was shown that one can use partial correlation coefficients in order to estimate strength and direction of a linear relationship between the variables used to characterize properties of nuclear matter. This method can be used to analyse data coming from both experiments and simulations.