The effects of distance and variation on product-category similarity judgments are examined in two studies. Distance between product categories is characterized as the mean difference in the average scores of all brands in one category with all brands in another on a comparison attribute. Variation is characterized as a degree of spread of brands along that comparison attribute. Study 1 finds that both distance and variation influence the perceived similarity of two product categories. An interaction between distance and variation is also observed. Study 2 is designed to replicate and extend these results, determining if distance and variation also affect similarity judgments when brands in the two product categories are not described by the same attribute -but instead where a comparison attribute must be abstracted. The results confirm the main effects of distance and variation. However, the interaction effects between distance and variation disappear, suggesting that subjects lose some information about distribution knowledge in the abstraction process. Both studies support consumers' use of distribution knowledge about brands (distance and variation) in productcategory similarly judgment tasks. ᭧ 2004 Wiley Periodicals, Inc.
YOO AND MACINNISConsiderable research has supported the effect of similarity between brands and product categories on consumers' brand judgments (Johnson & Horne, 1992). Similarity among brands within a product category, for example, has been found to affect the perceived positioning of products (Aaker & Shansby, 1982;Arabie, Carroll, DeSarbo & Wind, 1981;Dube & Schmitt, 1999;Viswanathan & Childers, 1999) and the extent to which brands are perceived as close to or far from a prototypical brand (Loken & Ward, 1990). Similarity of brands across categories has been found to affect cross-category competition (Ratneshwar & Shocker, 1991), the extent to which brands are regarded as "comparable" (Bettman & Sujan, 1987;Johnson, 1984Johnson, , 1988Johnson, , 1989Park & Smith, 1989), and the extent to which brand extensions are judged as favorable (e.g., Aaker & Keller, 1990;Boush, 1993;Boush & Loken, 1991;Dacin & Smith, 1993;Keller & Aaker, 1992;Park, Milberg, & Lawson, 1991).
Distance and Variation under Product-Category Similarity Judgment TaskDespite the importance of similarity judgments to marketing and consumer behavior, theoretical models about the factors that drive similarity judgments are scarce. A common assumption of research in this area has been that the closer two brands are in terms of a common attribute or a set of common attributes, the more similar they are perceived to be. As such, the distance between two brands drives similarity judgments. Although distance might be conceptualized as interpoint distance between two brands on a similar attribute, similarity judgments could also be affected by context (Tversky, 1977). A different conceptualization of distance could be conceived when consumers compare two different product categories. In this situation, context could be ...
