X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=doc%2Fstatistics.texi;h=599e7e42903bab70945735e8f455232af8230886;hb=631e2243322503338b497cd13529fbb2c5833e3d;hp=0cb7f70fe84e59d662bee2bbb220a15822e48038;hpb=7ebdbb57cdb7f8e9413cccc0426d6cd6af3d98b9;p=pspp-builds.git diff --git a/doc/statistics.texi b/doc/statistics.texi index 0cb7f70f..599e7e42 100644 --- a/doc/statistics.texi +++ b/doc/statistics.texi @@ -38,7 +38,7 @@ DESCRIPTIVES @{A,D@} @end display -The @cmd{DESCRIPTIVES} procedure reads the active file and outputs +The @cmd{DESCRIPTIVES} procedure reads the active dataset and outputs descriptive statistics requested by the user. In addition, it can optionally compute Z-scores. @@ -681,10 +681,15 @@ is used. @menu * BINOMIAL:: Binomial Test * CHISQUARE:: Chisquare Test +* COCHRAN:: Cochran Q Test +* FRIEDMAN:: Friedman Test +* KENDALL:: Kendall's W Test * KRUSKAL-WALLIS:: Kruskal-Wallis Test -* WILCOXON:: Wilcoxon Signed Ranks Test +* MANN-WHITNEY:: Mann Whitney U Test +* MCNEMAR:: McNemar Test * RUNS:: Runs Test * SIGN:: The Sign Test +* WILCOXON:: Wilcoxon Signed Ranks Test @end menu @@ -765,9 +770,53 @@ If no /EXPECTED subcommand is given, then then equal frequencies are expected. +@node COCHRAN +@subsection Cochran Q Test +@vindex Cochran +@cindex Cochran Q test +@cindex Q, Cochran Q + +@display + [ /COCHRAN = varlist ] +@end display + +The Cochran Q test is used to test for differences between three or more groups. +The data for @var{varlist} in all cases must assume exactly two distinct values (other than missing values). + +The value of Q will be displayed and its Asymptotic significance based on a chi-square distribution. + +@node FRIEDMAN +@subsection Friedman Test +@vindex FRIEDMAN +@cindex Friedman test + +@display + [ /FRIEDMAN = varlist ] +@end display + +The Friedman test is used to test for differences between repeated measures when there is no indication that the distributions are normally distributed. + +A list of variables which contain the measured data must be given. The procedure prints the sum of ranks for each variable, the test statistic and its significance. + +@node KENDALL +@subsection Kendall's W Test +@vindex KENDALL +@cindex Kendall's W test +@cindex coefficient of concordance + +@display + [ /KENDALL = varlist ] +@end display + +The Kendall test investigates whether an arbitrary number of related samples come from the +same population. +It is identical to the Friedman test except that the additional statistic W, Kendall's Coefficient of Concordance is printed. +It has the range [0,1] --- a value of zero indicates no agreement between the samples whereas a value of +unity indicates complete agreement. + + @node KRUSKAL-WALLIS @subsection Kruskal-Wallis Test -@comment node-name, next, previous, up @vindex KRUSKAL-WALLIS @vindex K-W @cindex Kruskal-Wallis test @@ -790,20 +839,38 @@ of the test will be printed. The abbreviated subcommand K-W may be used in place of KRUSKAL-WALLIS. -@node WILCOXON -@subsection Wilcoxon Matched Pairs Signed Ranks Test -@comment node-name, next, previous, up -@vindex WILCOXON -@cindex wilcoxon matched pairs signed ranks test +@node MANN-WHITNEY +@subsection Mann-Whitney U Test +@vindex MANN-WHITNEY +@vindex M-W +@cindex Mann-Whitney U test +@cindex U, Mann-Whitney U @display - [ /WILCOXON varlist [ WITH varlist [ (PAIRED) ]]] + [ /MANN-WHITNEY = varlist BY var (group1, group2) ] @end display -The /WILCOXON subcommand tests for differences between medians of the -variables listed. -The test does not make any assumptions about the variances of the samples. -It does however assume that the distribution is symetrical. +The Mann-Whitney subcommand is used to test whether two groups of data come from different populations. +The variables to be tested should be specified in @var{varlist} and the grouping variable, that determines to which group the test variables belong, in @var{var}. +@var{Var} may be either a string or an alpha variable. +@var{Group1} and @var{group2} specify the +two values of @var{var} which determine the groups of the test data. +Cases for which the @var{var} value is neither @var{group1} or @var{group2} will be ignored. + +The value of the Mann-Whitney U statistic, the Wilcoxon W, and the significance will be printed. +The abbreviated subcommand M-W may be used in place of MANN-WHITNEY. + +@node MCNEMAR +@subsection McNemar Test +@vindex MCNEMAR +@cindex McNemar test + +@display + [ /MCNEMAR varlist [ WITH varlist [ (PAIRED) ]]] +@end display + +Use McNemar's test to analyse the significance of the difference between +pairs of correlated proportions. If the @code{WITH} keyword is omitted, then tests for all combinations of the listed variables are performed. @@ -817,6 +884,10 @@ If the @code{WITH} keyword is given, but the of variable preceding @code{WITH} against variable following @code{WITH} are performed. +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. + @node RUNS @subsection Runs Test @vindex RUNS @@ -863,6 +934,33 @@ If the @code{WITH} keyword is given, but the of variable preceding @code{WITH} against variable following @code{WITH} are performed. +@node WILCOXON +@subsection Wilcoxon Matched Pairs Signed Ranks Test +@comment node-name, next, previous, up +@vindex WILCOXON +@cindex wilcoxon matched pairs signed ranks test + +@display + [ /WILCOXON varlist [ WITH varlist [ (PAIRED) ]]] +@end display + +The /WILCOXON subcommand tests for differences between medians of the +variables listed. +The test does not make any assumptions about the variances of the samples. +It does however assume that the distribution is symetrical. + +If the @code{WITH} keyword is omitted, then tests for all +combinations of the listed variables are performed. +If the @code{WITH} keyword is given, and the @code{(PAIRED)} keyword +is also given, then the number of variables preceding @code{WITH} +must be the same as the number following it. +In this case, tests for each respective pair of variables are +performed. +If the @code{WITH} keyword is given, but the +@code{(PAIRED)} keyword is omitted, then tests for each combination +of variable preceding @code{WITH} against variable following +@code{WITH} are performed. + @node T-TEST @comment node-name, next, previous, up @section T-TEST @@ -1003,7 +1101,7 @@ ONEWAY /MISSING=@{ANALYSIS,LISTWISE@} @{EXCLUDE,INCLUDE@} /CONTRAST= value1 [, value2] ... [,valueN] /STATISTICS=@{DESCRIPTIVES,HOMOGENEITY@} - + /POSTHOC=@{BONFERRONI, GH, LSD, SCHEFFE, SIDAK, TUKEY, ALPHA ([value])@} @end display The @cmd{ONEWAY} procedure performs a one-way analysis of variance of @@ -1047,6 +1145,29 @@ A setting of EXCLUDE means that variables whose values are user-missing are to be excluded from the analysis. A setting of INCLUDE means they are to be included. The default is EXCLUDE. +Using the @code{POSTHOC} subcommand you can perform multiple +pairwise comparisons on the data. The following comparison methods +are available: +@itemize +@item LSD +Least Significant Difference. +@item TUKEY +Tukey Honestly Significant Difference. +@item BONFERRONI +Bonferroni test. +@item SCHEFFE +Scheff@'e's test. +@item SIDAK +Sidak test. +@item GH +The Games-Howell test. +@end itemize + +@noindent +The optional syntax @code{ALPHA(@var{value})} is used to indicate +that @var{value} should be used as the +confidence level for which the posthoc tests will be performed. +The default is 0.05. @node RANK @comment node-name, next, previous, up