Construction of the Global ${\chi }^2$ Function for the Simultaneous Fitting of Correlated Energy-Dependent Cross Sections

In this paper, the global ${\chi }^2$ function for the simultaneous fitting of correlated energy-dependent cross sections is constructed, where the correlations between the measured cross sections of different processes and/or at different center-of-mass energy points, as well as the contributions from the integrated luminosity measurement and the center-of-mass energy measurement, are taken into account.