title: A nonparametric version of Williams' test for a randomized block design.
abstract: A large-sample nonparametric version of Williams' test for comparing increasing doses of a substance with a zero-dose control response is given for observations from a randomized block experimental design. The method is based on Friedman-type ranks. Williams' test and the nonparametric equivalent for a one-way design are briefly described. The validity of the new method is shown and a numerical example is given.
mesh_terms: D000818:Animals; D004305:Dose-Response Relationship, Drug; D064420:Drug-Related Side Effects and Adverse Reactions; D008954:Models, Biological; D011897:Random Allocation; D012107:Research Design