PLOT Subcommand (CATREG command)

The PLOT subcommand controls the display of plots.

  • The REGU keyword is only applicable if a REGULARIZATION method is specified.
  • In this subcommand, if no plot keyword is given, then no plot is created. Further, if the variable list following the plot keyword is empty, then no plot is created, either.
  • All of the variables to be plotted must be specified in the ANALYSIS subcommand. Further, for the residual plots, the variables must be independent variables.

    TRANS(varlist)(l). Transformation plots (optimal category quantifications against category indicators). A list of variables must come from the ANALYSIS variable list and must be given in parentheses following the keyword. Further, the user can specify an optional parameter l in parentheses after the variable list in order to control the global upper boundary of category label lengths in the plot. Note that this boundary is applied uniformly to all transformation plots.

    RESID(varlist)(l). Residual plots (residuals when the dependent variable is predicted from all predictor variables in the analysis except the predictor variable in varlist, against category indicators, and the optimal category quantifications multiplied with beta against category indicators). A list of variables must come from the ANALYSIS variable list’s independent variables and must be given in parentheses following the keyword. Further, the user can specify an optional parameter l in parentheses after the variable list in order to control the global upper boundary of category label lengths in the plot. Note that this boundary is applied uniformly to all residual plots.

    REGU(valuelist). Ridge, Lasso, or Elastic Net plots, depending on the regularization method specified at the REGULARIZATION subcommand. A value or valuelist of Ridge penalties must be given in parentheses following the keyword if the regularization method is Elastic Net. The Elastic Net method results in multiple plots: a Lasso plot for each value of the Ridge penalty. To obtain all Elastic Net plots, the keyword ALL in stead of a valuelist can be used.

  • The category label length parameter (l) can take any non-negative integer less than or equal to 60. If l = 0, values instead of value labels are displayed to indicate the categories on the x axis in the plot. If l is not specified, CATREG assumes that each value label at its full length is displayed as a plot’s category label. If l is an integer larger than 60, then we reset it to 60 but do not issue a warning.
  • If a positive value of l is given but if some or all of the values do not have value labels, then for those values, the values themselves are used as the category labels.
  • The keyword TO in a variable list can be used only with variables that are in the ANALYSIS subcommand, and TO applies only to the order of the variables in the ANALYSIS subcommand. For variables that are in the VARIABLES subcommand but not in the ANALYSIS subcommand, the keyword TO cannot be used. For example, if /VARIABLES = v1 TO v5 and /ANALYSIS is v2 v1 v4, then /PLOT TRANS(v1 TO v4) will give two transformation plots, one for v1 and for v4. (/PLOT TRANS(v1 TO v4 v2 v3 v5) will give transformation plots for v1, v2, v3, v4, and v5.)