Psychology of Space Exploration
Despite the apparent support that task cohesion and, to a lesser extent, inter-
personal cohesion positively influence team and group performance, part of the dif-
ficulty in defining the cohesion-performance effect is attributed to the influence of
moderator variables. C. R. Evans and K. Dion, in their meta-analyses of over 372
groups, showed that group cohesion led to increased performance; however, the
effect was relatively small and appeared to depend on other factors.^35 One example
is A. Tziner and Y. Vardi’s finding that for three-person tank crews, performance,
effectiveness, and cohesiveness were correlated only when studied in combination
with the command style of tank commanders. Highly cohesive teams exhibited bet-
ter performance only if the command style emphasized an orientation toward the
task and the team members. For command styles only emphasizing team member
orientation, low cohesiveness was related to better performance.^36 Another perspec-
tive is that cohesion is associated with performance, but that high levels of team
cohesion may negatively affect a team, as in the case of groupthink or in teams
whose norms do not support productivity.^37 If the predominate group norm is a slow
work pace, cohesiveness might actually reduce performance.
Similar to the effect of moderator variables, another complicating factor in
studying the cohesion-performance effect is determining which comes first. There
remains significant controversy over the causal nature of the relationship. In the
sports domain, Daniel Landers, Michael Wilkinson, Brad Hatfield, and Heather
Barber commented, “Even when the same measuring instruments are employed for
interacting team sports, some studies demonstrate a reciprocal causality between
the two variables (i.e., cohesion affects performance outcome and vice versa),
whereas other studies find that performance outcome affects cohesion, but cohe-
sion does not influence performance.”^38
- C. R. Evans and K. Dion, “Group Cohesion and Performance: A Meta-analysis,” Small
Group Research 22, no. 2 (1991):175–186. - A. Tziner and Y. Vardi, “Ability as a Moderator Between Cohesiveness and Tank Crew’s
Performance,” Journal of Occupational Behavior 4 (1983): 137–143. - T. W. Porter and B. S. Lilly, “The Effects of Conflict, Trust, and Task Commitment on
Project Team Performance,” International Journal of Conflict Management 7, no. 4 (1996):
361–376. - Daniel M. Landers, Michael O. Wilkinson, Brad D. Hatfield, and Heather Barber,
“Causality and the Cohesion-Performance Relationship,” Journal of Sport Psychology 4, no. 2
(1982): 170–183.