Positional RA (red) and Dec (blue) offsets of the LOFAR sources compared to VIDEO sources (Jarvis et al. 2013). Panel a: histogram for all matches within 10″; panel b: histogram of offsets for the best-matched VIDEO source for each LOFAR source that had a VIDEO source within 10″. The upper left shows the median offsets and the errors associated with these from the 16th and 84th percentiles. The dashed line indicates the median offset value for either the RA offsets (red) or Dec offsets (blue). Offsets are defined as RA_LOFAR–R_VIDEO and similar for Dec.