A nonparametric test for a multi-sample scale problem using ranked-set data

A nonparametric test for the several-sample scale problem is proposed, based on ranked-set data. The proposed test has the advantage of not requiring the several distribution functions to have a common median, but rather any common quantile of order αα, 0<α<10<α<1 (not necessarily 1/21/2), which is assumed to be known. It is shown that the new test is uniformly more efficient than its simple random sample analog.