Basic Analysis and Graphing - SAS

152 Performing Oneway Analysis Chapter 5
Nonparametric
Table 5.13 Descriptions of Nonparametric Tests
Wilcoxon Test a
Median Test
van der Waerden Test
Kolmogorov-Smirnov Test
Exact Test
Performs the test based on Wilcoxon rank scores. The Wilcoxon rank
scores are the simple ranks of the data. The Wilcoxon test is the most
powerful rank test for errors with logistic distributions. If the factor has
two or more levels, the Kruskal-Wallis test is performed.
The Wilcoxon test is also called the Mann-Whitney test.
Performs the test based on Median rank scores. The Median rank scores
are either 1 or 0, depending on whether a rank is above or below the
median rank. The Median test is the most powerful rank test for errors
with double-exponential distributions.
Performs the test based on Van der Waerden rank scores. The Van der
Waerden rank scores are the ranks of the data divided by one plus the
number of observations transformed to a normal score by applying the
inverse of the normal distribution function. The Van der Waerden test is
the most powerful rank test for errors with normal distributions.
Performs the test based on the empirical distribution function, which
tests whether the distribution of the response is the same across the
groups. Both an approximate and an exact test are given. This test is
available only when the X factor has two levels.
Provides options for performing exact versions of the Wilcoxon, Median,
van der Waerden, and Kolmogorov-Smirnov tests. These options are
available only when the X factor has two levels, and after the
approximate test is requested.