Other plausible explanations for the fact that people frequently deny or hesitate to acknowledge their own social comparison activities is that people are possibly oblivious of the fact that they make comparisons (cf. Brickman & Bulman, 1977). Further, this reluctance may result from problems in selectivity, recall, and aggregation (cf. Helgeson & Taylor, 1993; Wood, 1996). Other reasons might be that individuals truly lack an interest in social comparison information or that they seldom do engage in social comparison. Thus, there may be individual differences in the tendency to compare oneself with others.

Indeed several researchers have already theorized that people may differ in their disposition to compare themselves with other people (e.g., Brickman and Bulman, 1977; Hemphill & Lehman, 1991; Taylor, Buunk, Collins, & Reed, 1992; Wills, 1981). For instance, Hemphill and Lehman (1991) mentioned "the need for researchers to include measures of social comparison that acknowledge the fact that people may not wish to compare with others to an equal extent" (p. 390). Possibly, when people explain their difficulties with social comparison questionnaires and declare that they never compare themselves to others, this may mean that they truly lack an interest in social comparison information, and thus are indeed not disposed to assess their own situation against that of others.

Recently, Gibbons and Buunk (1999) proposed the concept of social comparison orientation to refer to the personality disposition of individuals who are strongly oriented to social comparison, who have a tendency to relate what happens to others to themselves, who are interested in information about others' thoughts and behaviors in similar circumstances, and who concern themselves with their own standing relative to others. In a series of studies, Gibbons and Buunk (1999) demonstrated that social comparison orientation is related, among others, positively to self-consciousness, neuroticism, an anxious avoidant attachment style, and negatively to self-esteem, but not to social desirability (see also Helgeson & Taylor, 1993). In addition, comparison orientation is characteristic of individuals high in exchange orientation (i.e., a quid-pro-quo attitude) and high in communal orientation (i.e., an inclination to respond to other persons needs, and to expect others to do likewise).

According to Gibbons and Buunk, these findings suggest that individuals high in social comparison orientation are characterized by a heightened uncertainty about themselves, accompanied by a relatively strong dependency upon other people. Evidence for the external validity of the scale comes, among others, from a laboratory experiment showing that individuals high in social comparison orientation are more interested in the scores of others after having learned their own score (Gibbons & Buunk, 1999). From research among cancer patients it has been shown that patients high in social comparison orientation, when given the opportunity, were more inclined to attend to and select information about fellow patients' disease-related experiences, and that they respond more strongly to such information (Van der Zee, Oldersma, Buunk & Bos, 1998).

The current research explored the role of social comparison orientation by examining the extent to which the consequences of cognitive downward comparison and the reactions to overt downward comparison behavior are moderated by individuals' orientation toward social comparison. That is, because individuals high in this orientation are more uncertain about themselves and seem to use the standing of others as a basis for evaluating their own characteristics, it was assumed that downward comparison would have a stronger positive effect on individual's evaluation of the relationship and on commitment to the relationship the higher the individuals' orientation to social comparison.

More specifically, it was expected that the positive effect of downward comparison would be moderated by social comparison orientation in such a way that cognitive downward comparison will exert a stronger effect upon perceived relationship quality the higher the social comparison orientation. Furthermore, the impact of social comparison orientation on individuals' reactions to others engaging in public downward comparison was explored. That is, it was examined whether downward social comparison would be regarded as more socially inappropriate and undesirable by individuals high rather than low in social comparison orientation.