Existing models of group behavior, in a variety of fields, leave many open challenges. In particular, existing models often focus only on a specific phenomenon (e.g. flocking, pedestrian movement), and thus must be switched depending on the goals of the simulation. In contrast, we investigate a general cognitive model of simulating group behaviors, based on Festingers Social Comparison Theory (SCT), a prominent social psychology theory. In previous work, we have show SCT covers a variety of pedestrian movement phenomena. In this paper we present evidence for SCTs generality by describing the use of the SCT model (using the Soar cognitive architecture) in generation of imitational behavior in loosely-coupled groups. Since the imitational behavior does not have clear standards of evaluation, we propose a method for such evaluation. Based on experiments with human subjects, we show that SCT generates behavior more in-tune with human crowd behavior.