Normalized cumulative distribution for the numbers of ALL-XRBs (top), NS-XRBs (middle), and BH-XRBs (bottom), respectively. The thick-dotted and dashed lines represent the relative numbers of NS- and BH-XRBs contributing to ALL-XRBs, respectively. The thin-solid, dotted, and dashed lines represent the observed cumulative distributions of source displacements in galaxies M 82, NGC 1569, and NGC 5253 (see Fig. 2 in Kaaret et al. 2004), respectively. From left to right are models M1, M2, BAC, and M3.