CANCELLATION AND FOCUS - THE ROLE OF SHARED AND UNIQUE FEATURES IN THE CHOICE PROCESS

A feature matching comparison process was used to derive a model for p reference choices in which features shared by the choice alternatives are canceled and greater weight is placed on the unique features of th e alternative that is the starting point of the comparison. These aspe cts of the cancellation and focus model were tested in two experiments . In Experiment 1, after making a series of preference judgments betwe en paired items that either shared good features and had unique-bad fe atures (unique-bad pairs) or shared bad features and had unique-good f eatures (unique-good pairs), subjects evaluated both the chosen and re jected alternatives. As expected, for unique-good pairs the bad featur es of the alternatives were canceled, whereas for unique-bad pairs the good features were canceled, resulting in higher postchoice evaluatio ns of alternatives judged from unique-good pairs. In Experiment 2, the predicted advantage in postchoice evaluations of the products of uniq ue-good over unique-bad comparisons (derived from the cancellation asp ect of the model) was unaffected by whether the paired alternatives we re encountered sequentially or side by side. In contrast, the relative preference of the subject or referent of a pair (derived from the foc us aspect of the model) was eliminated when the choice alternatives we re encountered side by side rather than sequentially, because a side b y side comparison reduced the extent to which the features of the alte rnative under focus would be used to recruit features of the referent for use in the comparison. Implications of the cancellation-and-focus model of choice and its relation to other models of choice are discuss ed. (C) 1995 Academic Press, Inc.