UTILITY Subcommand (CONJOINT command)

UTILITY writes a utility file to the specified IBM® SPSS® Statistics file.

  • If UTILITY is not specified, no utility file is written.
  • UTILITY is followed by the name of the file to be written.
  • The file is specified in the usual manner for your operating system.
  • The utility file contains one case for each subject. If SUBJECT is not specified, the utility file contains a single case with statistics for the group as a whole.

The variables that are written to the utility file are in the following order:

  • Any SPLIT FILE variables in the active dataset.
  • Any SUBJECT variable.
  • The constant for the regression equation for the subject. The regression equation constant is named CONSTANT.
  • For DISCRETE factors, all of the utilities that are estimated for the subject. The names of the utilities that are estimated with DISCRETE factors are formed by appending a digit after the factor name. The first utility gets a 1, the second utility gets a 2, and so on.
  • For LINEAR factors, a single coefficient. The name of the coefficient for LINEAR factors is formed by appending _L to the factor name. (To calculate the predicted score, multiply the factor value by the coefficient.)
  • For IDEAL or ANTIIDEAL factors, two coefficients. The name of the two coefficients for IDEAL or ANTIIDEAL factors are formed by appending _L and _Q, respectively, to the factor name. (To use these coefficients in calculating the predicted score, multiply the factor value by the first coefficient and add that to the product of the second coefficient and the square of the factor value.)
  • The estimated ranks or scores for all profiles in the plan file. The names of the estimated ranks or scores are of the form SCORE n for experimental and holdout profiles, or SIMUL n for simulation profiles, where n is the position in the plan file. The name is SCORE for experimental and holdout profiles even if the data are ranks.

If the variable names that are created are too long, letters are truncated from the end of the original variable name before new suffixes are appended.