X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=doc%2Fstatistics.texi;h=63e8f35aef9ba37f540661aee7018c3b6a9fadb4;hb=bb025f49673d66a2e490a781d7d59b2f32da0087;hp=36c864eafca1b3f3053bb401782439bfddaa4b17;hpb=e358386a8422422d8dafabfb999a2cf4ef2b386e;p=pspp-builds.git diff --git a/doc/statistics.texi b/doc/statistics.texi index 36c864ea..63e8f35a 100644 --- a/doc/statistics.texi +++ b/doc/statistics.texi @@ -8,6 +8,7 @@ far. * DESCRIPTIVES:: Descriptive statistics. * FREQUENCIES:: Frequency tables. * EXAMINE:: Testing data for normality. +* CORRELATIONS:: Correlation tables. * CROSSTABS:: Crosstabulation tables. * NPAR TESTS:: Nonparametric tests. * T-TEST:: Test hypotheses about means. @@ -301,6 +302,69 @@ If many dependent variable are given, or factors are given for which there are many distinct values, then @cmd{EXAMINE} will produce a very large quantity of output. +@node CORRELATIONS +@section CORRELATIONS + +@vindex CORRELATIONS +@display +CORRELATIONS + /VARIABLES = varlist [ WITH varlist ] + [ + . + . + . + /VARIABLES = varlist [ WITH varlist ] + /VARIABLES = varlist [ WITH varlist ] + ] + + [ /PRINT=@{TWOTAIL, ONETAIL@} @{SIG, NOSIG@} ] + [ /STATISTICS=DESCRIPTIVES XPROD ALL] + [ /MISSING=@{PAIRWISE, LISTWISE@} @{INCLUDE, EXCLUDE@} ] +@end display + +@cindex correlation +The @cmd{CORRELATIONS} procedure produces tables of the Pearson correlation coefficient +for a set of variables. The significance of the coefficients are also given. + +At least one VARIABLES subcommand is required. If the WITH keyword is used, then a non-square +correlation table will be produced. +The variables preceding WITH, will be used as the rows of the table, and the variables following +will be the columns of the table. +If no WITH subcommand is given, then a square, symmetrical table using all variables is produced. + + +The @cmd{MISSING} subcommand determines the handling of missing variables. +If INCLUDE is set, then user-missing values are included in the +calculations, but system-missing values are not. +If EXCLUDE is set, which is the default, user-missing +values are excluded as well as system-missing values. +This is the default. + +If LISTWISE is set, then the entire case is excluded from analysis +whenever any variable specified in the any @cmd{/VARIABLES} subcommand +contains a missing value. +If PAIRWISE is set, then a case is considered missing only if either of the +values for the particular coefficient are missing. +The default is PAIRWISE. + +The PRINT subcommand is used to control how the reported significance values are printed. +If the TWOTAIL option is used, then a two-tailed test of significance is +printed. If the ONETAIL option is given, then a one-tailed test is used. +The default is TWOTAIL. + +If the NOSIG option is specified, then correlation coefficients with significance less than +0.05 are highlighted. +If SIG is specified, then no highlighting is performed. This is the default. + +@cindex covariance +The STATISTICS subcommand requests additional statistics to be displayed. The keyword +DESCRIPTIVES requests that the mean, number of non-missing cases, and the non-biased +estimator of the standard deviation are displayed. +These statistics will be displayed in a separated table, for all the variables listed +in any /VARIABLES subcommand. +The XPROD keyword requests cross-product deviations and covariance estimators to +be displayed for each pair of variables. +The keyword ALL is the union of DESCRIPTIVES and XPROD. @node CROSSTABS @section CROSSTABS @@ -960,7 +1024,7 @@ analysis tested against the totals. @display ROC @var{var_list} BY @var{state_var} (@var{state_value}) - /PLOT @{ CURVE [(REFERENCE)], NONE @} + /PLOT = @{ CURVE [(REFERENCE)], NONE @} /PRINT = [ SE ] [ COORDINATES ] /CRITERIA = [ CUTOFF(@{INCLUDE,EXCLUDE@}) ] [ TESTPOS (@{LARGE,SMALL@}) ] @@ -1013,8 +1077,11 @@ The default is FREE. @item The CUTOFF parameter is for compatibility and is ignored. @end itemize - The MISSING subcommand determines whether user missing values are to -be included or excluded in the analysis. The default behaviour is to exclude them. +be included or excluded in the analysis. The default behaviour is to +exclude them. +Cases are excluded on a listwise basis; if any of the variables in @var{var_list} +or if the variable @var{state_var} is missing, then the entire case will be +excluded.