Search for the maximum values of parameter s for which the IDP test isurvdiff(formula,...) issues a determinate decision. The function test values of s up to the parameter smax. If for smax the IDP test is still determinate, isurvdiff.smax returns list(smax,testout). If for s=0 the test is already indeterminate, isurvdiff.smax returns list(-1,testout), where testout is the last executed test.
Tests if there is a difference between two survival curves based on two samples (X and Y) with right censored data. More precisely it test whether the probabiliy P(X<Y) is greater than, lower than or equal to 1/2. The prior near-ignorance Dirichlet Process (IDP) rank sum test is used. It returns the result of the deicison. H=1 indicates that the alternative hypothesis is true with posterior probability greater than level. H=0 indicates the hypothesis is not true with posterior greater than level, H=2 indicates an indeterminate instance. This means that the decision depends on the choice of the prior.
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