title: Some tests for detecting trends based on the modified Baumgartner-Weiβ-Schindler statistics.
abstract: We propose a modified nonparametric Baumgartner-Weiβ-Schindler test and investigate its use in testing for trends amongKbinomial populations. Exact conditional and unconditional approaches top-value calculation are explored in conjunction with the statistic in addition to a similar test statistic proposed by Neuhäuser (2006), the unconditional approaches considered including the maximization approach (Basu, 1977), the confidence interval approach (Berger and Boos, 1994), and theE+Mapproach (Lloyd, 2008). The procedures are compared with regard to actual Type I error and power and examples are provided. The conditional approach and theE+Mapproach performed well, with theE+Mapproach having an actual level much closer to the nominal level. TheE+Mapproach and the conditional approach are generally more powerful than the otherp-value calculation approaches in the scenarios considered. The power difference between the conditional approach and theE+Mapproach is often small in the balance case. However, in the unbalanced case, the power comparison between those two approaches based on our proposed test statistic show that theE+Mapproach has higher power than the conditional approach.
authors.forename: Guogen
authors.initials: G
authors.lastname: Shan
authors.forename: Changxing
authors.initials: C
authors.lastname: Ma
authors.forename: Alan D
authors.initials: AD
authors.lastname: Hutson
authors.forename: Gregory E
authors.initials: GE
authors.lastname: Wilding
keywords: Baumgartner; E + M p-value; Exact Tests; Schindler test; Test for trend; Unconditional test; Weiβ