Exercise 3: Calculate the projected offset at which the probability of chance coincidence reaches 10% for galaxies with magnitudes of r = 21, 23, and 25 mag.  How does this compare to typical short GRB localizations?

With this caveat in mind, the projected offset distribution for short-duration GRBs is plotted in Figure 20.  Observed values to date range from 0.5-75 kpc, with a median of 5 kpc (i.e., 5x larger than long-duration GRBs).  Remarkably, the short-duration GRB offset distribution matches well with predictions from population synthesis models of binary neutron star mergers.