This study proposed that leader-member exchange (LMX) might encourage an employee to define job breadth close to or beyond the level of his/her supervisor's expectation (enlargement effect), while simultaneously fostering a reduction in supervisor-subordinate definition discrepancy on job content (congruence effect). Using data from 184 subordinate-supervisor dyads in Taiwan, we examined the relationships among LMX, job definition discrepancy, in-role/extra-role behaviour, and performance rating. Results showed that LMX was positively related to employee relative job breadth and the supervisor-subordinate congruence on job content, supporting the existence of enlargement effect and congruence effect. Additionally, employee relative job breadth was positively related to extra-role behaviour and the congruence on job content was positively related to in-role behaviour. However, neither in-role nor extra-role behaviour was related to performance rating. Theoretical and practical implications are discussed.
Journal of Occupational and Organizational Psychology, 82, 89-112