Distribution of the broken power-law spectral indices for the subsets of the RxAGN sample. Black crosses are spectral indices derived for individual bins, listed in Table 1. Blue intervals denote α₁ while orange intervals denote α₂. The distributions of the broken power-law spectral indices are used to determine the parameters that explain the differences between the RxAGN subsets using the ANOVA method summarized in Table 2.