Analysis of the Δ₂ distribution using GMM. First panel: BIC as a function of the number of Gaussian components considered in the GMM. Second panel: histogram of the Δ₂ distribution fitted with a two-Gaussian model (black continuous line). The two components of the two-Gaussian model are plotted as blue and red dashed lines. Third and fourth panels: distribution of the ratio of the two populations obtained from 1000 repetitions of the GMM fitting process. The reported values represent the median and standard deviation of the distribution.