Work Group Diversity and Social Cohesion: Exploring the Curvilinear Effects
Authors:   Asia-Europe Perspective Association, Seong Jee Young 
Published: June 2018

This study extends and enhances explanations of how work group diversity is associated with social cohesion in teams. This study developed a framework to predict social cohesion as viewed from social categorization and information-decision making perspectives, and proposes that work group diversity influences important team outcomes. The study examined the effect of three dimensions of diversity― age, gender and rank (hierarchical status)―on social cohesion in 27 teams of a marine transport company in South Korea. Previous research on the relationship between work group diversity and group outcomes has produced inconsistent results. This study addresses this issue by examining the relationship between work group diversity and social cohesion that is particularly relevant when considering group composition. It examined the possibility that the relationship between work group diversity and social cohesion is curvilinear in nature.
The results showed that there exists an inverted U-shaped curvilinear relationship between rank diversity and group social cohesion. As rank diversity increases, the intensity of social cohesion at the group level is raised, but only up to a certain point and beyond that, social cohesion is expected to reduce. This result implies that a high level of rank diversity does not necessarily guarantee a high level of group social cohesion. As to the effect of age diversity and gender diversity on group social cohesion, no significant curvilinear relationship was found between both age and gender diversity and social cohesion.
The interaction effect of age diversity and gender diversity on group social cohesion was found significant. Age diversity and gender diversity interacted to affect group social cohesion in such a way that the effect of age diversity on group social cohesion was stronger when gender diversity is low than when gender diversity is high. However, the interaction effect of gender diversity and rank diversity on group social cohesion was only marginally significant, and the interaction effect of age diversity and rank diversity was statistically insignificant. The effect of gender diversity on group social cohesion is much greater when age diversity is high than when age diversity is low. In other words, when gender diversity is low, groups with higher age diversity show much lower level of group social cohesion than the groups with lower age diversity. But when gender diversity is high, little difference was found between low and high age diversity groups in their social cohesion.
In sum, this study reported an inverted U-shaped relationship between work group diversity and social cohesion. After passing that peak of rank diversity, higher rank diversity does not enhance, but hampers, the degree of group social cohesion. This study also attempted to examine whether sub-dimensions of socio-demographic diversity interactively affect group outcomes. The results indicated that age diversity and gender diversity interact to affect group social cohesion. The interaction effect of age diversity and gender diversity on group social cohesion needs more explanation.
The results of this study rendered interesting implications for future research into the effects of demographic diversity on group outcomes. It provided an alternative way of explaining the effect of diversity in work teams on group social cohesion. In the context of work group diversity, this study focused on the interaction of different dimensions of diversity. It contributes to the literature on both diversity and group cohesion. Theoretically, this study combined the information/decision-making and social categorization perspectives into the categorization-elaboration model (CEM). With respect to diversity, demographic diversity constitutes a valuable source of variability. The synergistic effect of sub-dimensions of demographic diversity catalyzes group social cohesion.