Impact of group support systems on judgment biases: an experimental investigation
Creators: name: Lim, Lai-Huat
Publisher: name: University of British Columbia
Year: 2009

description: Past research has demonstrated that individual and group judgments are subject to systematic biases. Although much effort has been devoted to the debiasing of individual judgments, no corresponding work to date has been found on the debiasing of group judgments. Complicating this research gap is the fact that group and team work is gaining increasing importance in organizational settings. The current study examines the usefulness of group support systems (GSS) in addressing two important judgment biases, namely, representativeness bias and availability bias. Representativeness bias refers to the bias incurred in posterior-probability estimation by not properly utilizing information sources such as base rate. Availability bias occurs when events of higher availability to the memory are correspondingly judged as occurring more frequently. The formation of a judgment is seen from the perspective of an information integration process. Two orthogonal dimensions of information integration -- interpersonal and intrapersonal -- are involved in group judgments. Interpersonal information integration concerns the aspect of information sharing among group members, and can be supported with the electronic communication channel of GSS. Intrapersonal information integration deals with the information processing capacities and capabilities of individuals, and is supportable using cognitive-support tools of GSS. A laboratory experiment with a 2x2 factorial design was conducted. One hundred and twenty subjects took part in the experiment. They were randomly allocated to 40 groups. Two experimental tasks, designed to examine the two judgment biases of interest, were solved by each group. Data pertaining to both processes and outcomes were collected and analyzed. Representativeness bias was reduced by the use of cognitive support, in the form of a problem representation tool. Groups with the problem representation tool made fewer references to diagnostic information versus base rate, leading to the use of more correct strategies which combined these two information sources. The use of the problem representation tool was found to be responsible for causing this chain of events. On the other hand, electronic communication did not lead to a similar change in the pattern of group processes, and, correspondingly, did not reduce the representativeness bias. Although electronic communication is capable of improving the interpersonal aspect of information integration, the representativeness bias is primarily a result of cognitive limitations, and benefits little from improved communication among group members. Availability bias was reduced by both cognitive support and communication support. Cognitive support, in the form of electronic brainstorming, increased the information search scope of issues, especially those issues of relatively low availability to the memory. Electronic communication allows parallel input and has a lower social presence than verbal communication. These features helped to reduce the extent of groupthink and widened the range of alternative solutions proposed. Some interaction effects were observed on group members’ perceptions of the group process. For example, communication medium had an effect on group members’ satisfaction in groups without cognitive support, but not those with cognitive support. Correspondingly, cognitive support affected some perceptual variables in verbally-communicating groups, but not electronically-communicating groups. Examples of such effects include an increase in perceived socio-emotional behavior and perceived informal leadership.