The Rank-Order Effect in Group Decision Making

Abstract

Many studies indicate that group discussion candisproportionately reflect information known by all group members,at the expense of information known to only one group member, andthis is associated with suboptimal group decisions (Stasser &Titus, 1985). The present study examined the impact of threeprocedural factors on information sharing and quality of groupdecision: (a) group decision procedure (an instruction to "rankorder the alternatives" vs "choose the best alternative"), (b)information access during group discussion (reliance on memory vscomplete access), and (c) communication technology (computer vsface to face). Three-person groups worked on an investment decisionthat was structured as a hidden-profile task where criticalinformation was distributed unevenly prior to group discussion. Thedata provided support for a rank-order effect: Groups instructedto rank order the alternatives, compared to groups instructed tochoose the best alternative, were more likely to fully consider allof the alternatives, exchange information about unpopularalternatives, and make the best decision. But these effects onlyoccurred in face-to-face groups. In computer-mediated groups, therewas general information suppression and no effect of group decisionprocedure. Access to information during group discussion increaseddiscussion of both unique and common information, in theface-to-face conditions, but had no effect on group decisionquality. Taken together, the data suggest that procedural aspectsof group discussion may help overcome the impact of prediscussionpreferences on information processes and group decision.