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15.4 CORRELATIONS

     CORRELATIONS
          /VARIABLES = var_list [ WITH var_list ]
          [
           .
           .
           .
           /VARIABLES = var_list [ WITH var_list ]
           /VARIABLES = var_list [ WITH var_list ]
          ]
     
          [ /PRINT={TWOTAIL, ONETAIL} {SIG, NOSIG} ]
          [ /STATISTICS=DESCRIPTIVES XPROD ALL]
          [ /MISSING={PAIRWISE, LISTWISE} {INCLUDE, EXCLUDE} ]

The 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 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.

If LISTWISE is set, then the entire case is excluded from analysis whenever any variable specified in any /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.

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.