1、Week Five Non-parametric tests for independent deal with ranked data; analyse the relative location of the populations studied (medians). In testing the locations we will not refer to any parameter, thus the procedures name. Nonparametric methods can replace the parametric methods used for numerical
2、 data when the population is not normal. In nonparametric tests we hypothesise on the population locations (not necessarily their means).Two populations same location Two populations different locationsWilcoxon rank sum test for independent samples The problem characteristics this test is dealing wi
3、th are: the problem objective is to compare two populations the data are either ranked or numerical, but not normal the samples are independent. Ranking tests deal with “locations” rather than mean values. If two populations share the same location they are, in effect, a single population. Another way of saying it is that we are comparing two distributions of data. Null hypothesis: The null hypothesis is that two distributions are identical.SPSS两独立 样本非参数检验(一 )目的 由独立样本数据推断两总体的分布是否存在显著差异 (或两样本是否来自同一总体 )。 (二 )基本假设 H0:两总体分布无显著差异 (两样本来自同一总体 )(三 )数据要求 样本数据和分组标志
