Job Scope and Commitment: The Moderating Role of Support and Leader-Member Exchange

This study examines the moderating effect of the relational context of jobs on the relationship between job characteristics and affective commitment towards the organization, the occupation and customers. The relational context is captured through perceived organizational support and leader-member exchange. We hypothesized that perceived organizational support would fill employees’ socio-emotional needs and represent a sympathetic concern and indulgence from the organization toward employees. In contrast, leader-member exchange reflects a social exchange perspective in which the supervisor’s support is associated with the aim of improving employee performance. These considerations lead to expecting perceived organizational support to act as a negative moderator of the relationships of job characteristics (job scope) to affective commitment to the three targets of interest. On the contrary, we predict that leader-member exchange will act a positive moderator of the effects of job scope on affective commitments. These hypotheses were tested in a study involving two measurement times. Job scope (i.e., a summary measure of task variety, significance, autonomy, identity, and feedback; Hackman and Oldham, 1980), perceived organizational support, and leader-member exchange, were measured at Time 1, while affective commitment to the organization, the occupation, and customers was assessed six months later. Based on a random sample of 208 employees who graduated in business, law, engineering, and basic science in a Belgian University and were employed in a variety of organizations, moderated multiple regression analyses found the (positive) relationship of job scope to commitment to the three targets of interest to be weaker at high levels of perceived organizational support. In contrast, the (positive) relationship of job scope to affective commitment to the occupation and customers was stronger at high levels of leader-member exchange. We discuss the implications of these findings