Optionalalternative"two.sided" (default), "increasing" or "decreasing" (unambiguous abbreviations accepted).
OptionalexactThe exact p-value ("DescTools" only). Default: exact when there are no ties and at most 100 observations. With
ties the normal approximation is used anyway, with a warning. The exact distribution is the convolution of the
Mann-Whitney distributions; where it would have more than 2^24 values or take more than 2^32 multiply-adds
(three equal groups of 216, about 8 s), exact: true is a RangeError (R computes it however long it takes).
OptionallevelsThe order of the groups. Default: the labels sorted (numbers as numbers, strings by code point).
Optionalvariant"DescTools" (default: JonckheereTerpstraTest) or "clinfun" (jonckheere.test).
Options for jonckheereTest.