تعهد سازمانی اثرگذار و رفتار شهروندی : اثرات تعدیل خطی و غیرخطی دوران تصدی سازمانی

Utilizing a meta-analytical approach for testing moderating effects, the current study investigated organizational tenure as a moderator in the relation between affective organizational commitment and organizational citizenship behavior (OCB). We observed that, across 40 studies (N = 11,416 respondents), the effect size for the relation between affective organizational commitment and non-self measures of OCB was .23. However, we also found that organizational tenure moderated the relation in a non-linear way. Before 10 years of tenure, the strength of the commitment–OCB relation increased as organizational tenure increased; after that point, the strength of the commitment–OCB relation decreased as organizational tenure increased. In short, the moderating effect of tenure follows a curvilinear pattern.

In recent years, many organizations have tried to cultivate a workforce that is not only strongly committed to its employers but also strives for high performance (Deery and Iverson, 2005 and Rousseau, 1998). In academic research, the relation between organizational commitment and employee performance has also generated a great deal of interest among scholars (Jaramillo et al., 2005 and Riketta, 2002). Compared to non-committed workers, employees with high organizational commitment have been found to have more positive job attitudes and to exhibit stronger performance on the job (Harrison et al., 2006 and Meyer et al., 2002). Wright and Bonett (2002) argue that the commitment–performance relation deserves more attention because there are likely to be moderators of that relation. In particular, they found support for their prediction that tenure would moderate the relation such that committed workers with shorter tenure were likely to perform more strongly than committed workers with longer tenure. That is, as average tenure increases, the strength of the positive commitment–performance relation decreases. The current study extends Wright and Bonett's (2002) work in several ways. First, in the Wright and Bonett (2002) study, the focus was on in-role job performance. However, beyond core job duties, committed workers are also likely to go the extra mile and perform tasks that are not necessarily expected by others, such as helping out coworkers. Indeed, since going beyond the call of duty is largely left to the discretion of workers themselves, we might expect that the impact of commitment on these citizenship behaviors might be even greater than its impact on in-role performance. Organizational citizenship behaviors (OCB) are extremely important for promoting organizational performance (Podsakoff, Blume, Whiting, & Podsakoff, 2009). In fact, Lievens, Conway, and De Corte (2008) found that, in many situations, raters of job performance gave greater weight to OCB than to in-role performance. Relying on the same meta-analytical approach that Wright and Bonett (2002) used, we extend their work by examining the moderating effect of organizational tenure in the relation between commitment and OCB. We are aware of no prior studies which have directly examined the moderating effects of organizational tenure in that relation. Second, while Wright and Bonett (2002) combined both self-ratings and others' ratings of job performance in their study, here we focus solely on others' ratings of OCB (supervisory and peer ratings) and objective measures. We chose this strategy because self-ratings of job performance may be positively biased, as employees tend to rate their own job performance significantly higher than others do because of self-serving biases (Harris & Schaubroeck, 1988). Researchers have found that there is a particularly strong self-inflation bias in self-ratings of OCB (Organ & Ryan, 1995), while it can be argued that supervisors and peers may give more objective ratings of OCB. Third, while Wright and Bonett (2002) examined the linear moderating effects of tenure in the commitment–performance relation, in the present study we examine its curvilinear moderating effects, too. As we will discuss in more detail later, there are reasons to expect that the strength of the relation between commitment and performance may weaken over time, including the depletion of personal resources used to contribute extra over an extended period of time (English, Morrison, & Chalon, 2010). Beyond extending Wright and Bonett's (2002) work, the current study also attempts to advance organizational commitment theory by examining curvilinear moderating effects. Most studies of organizational commitment examine linear moderating effects. These linear moderating effects occur when the strength of the commitment–outcome relation changes in one direction (either increases or decreases) along with changes in the value of the moderator. In contrast, a curvilinear moderating effect occurs when the strength of the commitment–outcome relation increases as the value of the moderator increases, but then decreases beyond a certain value of the moderator. (Another form of a curvilinear moderating effect occurs when the strength of the commitment–outcome relation decreases as the value of the moderator increases, but then increases beyond a certain value of the moderator.) Testing for both linear and non-linear moderating effects has theoretical and practical implications for commitment research. Theoretically speaking, we cannot draw conclusions about the linear moderating effects of organizational commitment without first considering potential curvilinear effects (cf. Cortina, 1993). Practically speaking, identifying the curvilinear moderating effects on the commitment–outcome relations could help managers identify the inflection points when employees' behaviors are most likely to change. In the present study, we expect that while organizational commitment may be a strong driver of OCB at the time of entry and the first few years of employment, the strength of that relation is likely to decline as organizational tenure increases.

In this study, notable differences in the strength and direction of the commitment–OCB relation are observed across different levels of tenure. Moreover, the association between affective organizational commitment and OCB is both linearly and non-linearly moderated by organizational tenure. Taken together, we hope that this article provides new insights into the complicated effects of organizational tenure on the relation between organizational commitment and work outcomes.