FIELDS Subcommand (GENLINMIXED command)

The FIELDS subcommand specifies the target, optional offset, and optional analysis (regression) weight.

  • This subcommand, and the TARGET keyword, are required.
  • A field can only be specified once on the FIELDS subcommand.
  • A categorical TARGET can be specified as a GROUPING field on the DATA_STRUCTURE or RANDOM subcommand, but not in any other capacity. Any other field specified on the FIELDS subcommand cannot be used on any other subcommand.

TARGET. The target field is what the model tries to predict. Specify a single field.

TRIALS = NONE** | VALUE(number) | FIELD(field). If the model response can be expressed as the number of events occurring within a number of trials, then the TARGET keyword specifies the number of events and TRIALS specifies the number of trials. Use VALUE with the number of trials in parentheses if the number of trials is fixed for all subjects and FIELD with a field name in parentheses if the number of trials varies across subjects and there is a field containing the number of trials.

The procedure automatically computes the ratio of the events field over the trials field or number. Technically, the procedure treats the events field as the target in the sense that predicted values and residuals are based on the events field rather than the events/trials ratio.

ANALYSIS_WEIGHT. The model uses analysis (regression) weights to account for differences in variability across levels of the target field. Specify a single continuous field.

OFFSET = NONE** | VALUE(value) | FIELD(field). The offset is a constant added to the intercept. Specify a continuous field or number.

  • Records with missing values on the OFFSET field are not used in the analysis.
  • Specifying a number when /FIXED USE_INTERCEPT = YES is equivalent to adding a constant to the intercept.
  • Specifying a number when /FIXED USE_INTERCEPT = NO is equivalent to fixing the intercept at the specified number.