  We report the discovery of 31 new redshifted broad absorption line quasars
(RSBALs) from the Sloan Digital Sky Survey (SDSS). The number of previously
known such objects is 19. The identification of the new objects was enabled by
calculating similarities between quasar spectra in the SDSS. Using these
similarities we look for the objects that are similar to the ones in the
original sample, visually inspecting only hundreds, out of over 160,000 spectra
considered. We compare the performance of several similarity measures, as well
as different methods of employing them, in finding the RSBALs. We find that
decision tree based similarities recover the most objects, and that an ensemble
of methods performs better than any single one. As the similarities are not
tailored for the specific problem of finding RSBALs, they could be used for
searching for other types of quasars. The similarities and the code for their
calculation are available online.
