 Like the spatial median, the pseudo–median is well defined for all distributions of random variables having dimension two or greater; for one-dimensional distributions, there exists some pseudo–median, which need not be unique, however.Like the median, the pseudo–median is defined for even heavy–tailed distributions that lack any (finite) mean.The one-sample Hodges–Lehmann statistic need not estimate any population mean, which for many distributions does not exist.