RESUMEN
A new theoretical analysis of individual differences and cross-situational consistency of behavior is proposed. The authors hypothesized that the social behavior of mice (Mus musculus) is determined by individual differences among animals in behavior emitted (i.e., actor effects), in behavior elicited from social partners (partner effects), and by unique responses of one animal to another (relationship effects). Each effect represents a distinct facet of individual differences with different psychological meaning; likewise, the cross-situational consistency of each effect has a distinct psychological meaning. Individual differences in behavior emitted were observed, and these actor effects were consistent longitudinally. Individual differences in behavior elicited from social partners were observed, and these partner effects were also consistent longitudinally. Unique responses to specific social partners also determined behavior but were inconsistent longitudinally. The theoretical importance of reconceptualizing the concepts of individual differences and cross-situational consistency in behavior is discussed. ((c) 2005 APA, all rights reserved).