Simplified computation of the multivariate permutation test for arbitrarily censored survival data

This paper points out that the permutational covariance matrix of the multivariate generalization 1,2 of Gehan's test 3 on censored survival data enjoys the useful property that a generalized inverse may be explicitly computed. This leads to an exceedingly simple formula for the test statistic. The ease of the resulting calculations is displayed with a brief example from exercise stress testing.