On errors of radio source position catalogs

In this paper, a new method of investigation of the external radio source position catalogs RSPCs stochastic errors is presented. Using this method the stochastic errors of nine recently published RSPCs were evaluated. It has been shown that the result can be affected by the systematic differences between catalogs if the latter are not accounted for. It was also found that the formal uncertainties of the source position in the RSPCs correlate with the external errors. We also investigated several topics related to the formal uncertainties and systematic errors of RSPC.