Relative Importance

The range of the utility values (highest to lowest) for each factor provides a measure of how important the factor was to overall preference. Factors with greater utility ranges play a more significant role than those with smaller ranges.

This table provides a measure of the relative importance of each factor known as an importance score or value. The values are computed by taking the utility range for each factor separately and dividing by the sum of the utility ranges for all factors. The values thus represent percentages and have the property that they sum to 100. The calculations, it should be noted, are done separately for each subject, and the results are then averaged over all of the subjects.

Note that while overall or summary utilities and regression coefficients from orthogonal designs are the same with or without a SUBJECT subcommand, importances will generally differ. For summary results without a SUBJECT subcommand, the importances can be computed directly from the summary utilities, just as one can do with individual subjects. However, when a SUBJECT subcommand is used, the importances for the individual subjects are averaged, and these averaged importances will not in general match those computed using the summary utilities.

The results show that package design has the most influence on overall preference. This means that there is a large difference in preference between product profiles containing the most desired packaging and those containing the least desired packaging. The results also show that a money-back guarantee plays the least important role in determining overall preference. Price plays a significant role but not as significant as package design. Perhaps this is because the range of prices is not that large.

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