British Journal of Social Psychology (2000), 39, 555±577 Printed in Great Britain# 2000 The British Psychological Society 555
Self-categorization, aåective commitment andgroup self-esteem as distinct aspects of socialidentity in the organization
Massimo BergamiUniversity of Bologna, Italy
Richard P. Bagozzi*Rice University, USAThe purpose of this study is to distinguish between cognitive, aåective andevaluative components of social identity in the organization and to show how thecomponents instigate behaviours that bene®t in-group members. A new scale formeasuring cognitive organizational identi®cation (i.e. self-categorization) isdeveloped and compared to a leading scale. Internal consistency, convergentvalidity, predictive validity and generalizability of the two scales are established ona sample of Italian (N ¯ 409) and Korean (N ¯ 283) workers. Next, convergentand discriminant validity for measures of organizational identi®cation, aåectivecommitment and group self-esteem are demonstrated. Then, two antecedents ofthese components of social identity are examined: organization prestige andorganization stereotypes. Finally, the mediating role of the components of socialidentity are investigated between the antecedents and ®ve forms of citizenshipbehaviours. The last three analyses are performed on the Italian (N ¯ 409) workers.Among other ®ndings, the results show that aåective commitment and self-esteemare the primary motivators of citizenship behaviours. Moreover, cognitiveidenti®cation performs as a central mediator between prestige and stereotypeson the one hand, and aåective commitment and self-esteem on the other.Identi®cation is thus an indirect determinant of citizenship behaviours.This study investigated social identity in a work organization.Membership in a workorganization is one of the most important group a¬liations a person has because itoccupies more time than is spent in other groups, and the person’s livelihooddepends on the organization’s fortunes and his or her quality of role performance.Social identity theory has been studied most often in the contexts of (1) arti®cialgroups where people are assigned randomly to treatments (e.g. Diehl, 1990;Ellemers, Wilke, & van Knippenberg, 1993; Tajfel, Billig, Bundy, & Flament,1971) ; (2) categories where people are grouped according to such shared attributesas ethnicity, nationality or subject major in the university (e.g. Crocker, Luhtanen,Blaine, & Broadnax, 1994; Salazar, 1983 ; Smith & Henry, 1996) ; and (3) such* Requests for reprints should be addressed to Prof. Richard P. Bagozzi, Rice University, GraduateSchool of Management and Department of Psychology, 6100 Main Street, Houston, TX 77005-1892, USA(e-mail : bagozzi!rice.edu).

556 Massimo Bergami and Richard P. Bagozzinaturally occurring small groups as sororities (e.g. Hogg, 1996; Smith & Tyler,1997). By contrast, much less is known about social identity in work organizations(e.g. Ouwerkerk, Ellemers, & de Gilder, 1999).Although some theoretical work has been performed in the organization context(Ashforth & Mael, 1989, 1996 ; Dutton, Dukerich, & Harquail, 1994), virtually noattention has been given to the dimensions of social identity, their measurement andtheir causes and eåects. These topics have recently taken centre stage in psychology,particularly with regard to experimentally formed groups (Ellemers, Kortekaas, &Ouwerkerk 1999). An investigation of social identity in a work organization can notonly replicate and show the generalizability of recent experimental research into thedimensionality of social identity, but it can also give insight into the role socialidentity plays in in-group favouritism and its dependence on group status and groupstereotypes in a naturalistic setting, thereby contributing to the ecological validity ofmeasures of social identity.Organizational identi®cation and organizational commitment are two componentsof one’s social identity in the organization. However, researchers diåer over themeaning of identi®cation and commitment and have at times confounded the two.For example, in an early in¯uential account, Foote (1951, p. 17) de®ned identi®cationas the ` appropriation of and commitment to a particular identity ’. Likewise, acommonly adopted de®nition of organizational commitment maintains that it is the` relative strength of an individual’s identi®cation with and involvement in aparticular organization’ (Mowday, Porter, & Steers, 1982, p. 27). Because leadingtheories predict that identi®cation and commitment have consequences fororganizations and their members (e.g. satisfaction, prosocial behaviours, turnover,productivity, stress), it is important to clarify exactly to what the concepts refer (e.g.Ashforth& Mael, 1989; Becker, 1992; Brown& Williams, 1984; Dutton et al., 1994;Hunt & Morgan, 1994; Mathieu & Zajac, 1990).Recently, Ellemers et al. (1999) did much to resolve the conceptual confusionamong diåerent aspects of social identi®cation. Starting with Tajfel’s (1978) classicde®nition of social identity, they proposed (at p. 372) that three componentscontribute to one’s social identity : `a cognitive component (a cognitive awareness ofone’s membership in a social groupÐself-categorization), an evaluative component (apositive or negative value connotation attached to this group membershipÐgroupself-esteem), and an emotional component (a sense of emotional involvement with thegroupÐaåective commitment)’. In addition to arguing for conceptual distinctionsamong the components of social identi®cation, Ellemers et al. demonstrated that thecomponents are empirically distinct and diåerentially aåected by relative status andsize of the group and the basis of group formation and that the aåective componentof identi®cation is the main determinant of in-group favouritism.The purpose of the present investigation roughly parallels that of Ellemers et al.’s(1999) experimental study. Speci®cally, our research is a ®eld investigation of socialidentity in a work organization. We begin with an analysis of a leading measure oforganization identi®cation and point out its conceptual limitations. At the same time,we propose new measures for the cognitive (i.e. self-categorization) component ofidenti®cation. Next, we consider aåective and evaluative aspects of social identity anddiscuss their diåerentiation from cognitive identi®cation. Two antecedents of social