Added an implementation of the median test

[pspp] / doc / statistics.texi

diff --git a/doc/statistics.texi b/doc/statistics.texi
index b1121b498c24af28ddda49d8163d00e45673c355..18cc79e7ace82bdd38e55b4908aaf64a5e8a47b3 100644 (file)
--- a/doc/statistics.texi
+++ b/doc/statistics.texi
@@ -691,6 +691,7 @@ is used.
 * KRUSKAL-WALLIS::          Kruskal-Wallis Test
 * MANN-WHITNEY::            Mann Whitney U Test
 * MCNEMAR::                 McNemar Test
 * KRUSKAL-WALLIS::          Kruskal-Wallis Test
 * MANN-WHITNEY::            Mann Whitney U Test
 * MCNEMAR::                 McNemar Test

+* MEDIAN::                  Median Test

 * RUNS::                    Runs Test
 * SIGN::                    The Sign Test
 * WILCOXON::                Wilcoxon Signed Ranks Test
 * RUNS::                    Runs Test
 * SIGN::                    The Sign Test
 * WILCOXON::                Wilcoxon Signed Ranks Test


@@ -931,6 +932,31 @@ The data in each variable must be dichotomous.  If there are more
 than two distinct variables an error will occur and the test will
 not be run.
 
 than two distinct variables an error will occur and the test will
 not be run.
 

+@node MEDIAN
+@subsection Median Test
+@vindex MEDIAN
+@cindex Median test
+
+@display
+     [ /MEDIAN [(value)] = varlist BY variable (value1, value2) ]
+@end display
+
+The median test is used to test whether independent samples come from 
+populations with a common median.
+The median of the populations against which the samples are to be tested
+may be given in parentheses immediately after the 
+/MEDIAN subcommand.  If it is not given, the median will be imputed from the 
+union of all the samples.
+
+The variables of the samples to be tested should immediately follow the @samp{=} sign. The
+keyword @code{BY} must come next, and then the grouping variable.  Two values
+in parentheses should follow.  If the first value is greater than the second,
+then a 2 sample test is performed using these two values to determine the groups.
+If however, the first variable is less than the second, then a @i{k} sample test is
+conducted and the group values used are all values encountered which lie in the
+range [@var{value1},@var{value2}].
+
+

 @node RUNS
 @subsection Runs Test
 @vindex RUNS
 @node RUNS
 @subsection Runs Test
 @vindex RUNS