Some social psychological effects of group decision rules.

This study examined the effects of group decision rules and decision outcomes on satisfaction with the outcomes, perceived fairness of the rules, and amount of rejection between majority members and deviates. Two hundred and seventy male subjects were led to believe that they belonged to groups, each of which consisted of a four-person majority and a lone deviate. The groups ostensibly made decisions by using a majority, dictatorial, or unanimity rule. Principal findings of the study were as follows: Subjects were more satisfied with decisions with which they agreed than with decisions with which they disagreed. The perceived fairness of the decision rules was primarily a function of the representativeness of the decision. Subjects felt the rule was fairer when it resulted in a decision that was representative of the preferences of most group members than when it resulted in a decision that was unrepresentative. Finally, mutual rejection occurred between majority members and the lone deviate. The strongest rejection, however, was by majority members toward the deviate in instances when, under the dictatorship and unanimity rules, the deviate was able to impose an unrepresentative decision on the majority. Findings are discussed partly in terms of the effects of outcomes on the perceived legitimacy of decision rules and the resulting feelings toward group members held to be responsible for implementation of the rules. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Psychological entrapment in group decision making: An assigned decision rule and a groupthink phenomenon.

Addressed interpersonal factors affecting group entrapment and also attempted to delineate a conceptual link between collective entrapment and I. L. Janis's (1972, 1982) notion of groupthink. Two experiments were conducted in which 3-person groups were assigned either majority or unanimity rule as an official consensus requirement for their initial decision. It was expected and confirmed that groups whose initial decision processes were guided by unanimity rule were entrapped more often to the chosen course of action than were groups with majority rule. The results also suggested that homogeneity of members' opinions at the outset of interaction and group's rationalization norm were responsible for the observed difference. Discussion is focused on the implications of these findings for administrative decision contexts and their conceptual link of the notion of groupthink. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Group negotiation: Effects of decision rule, agenda, and aspiration.

In this study we characterized small group negotiation as a mixed motive task that involved both cooperation and competition. We examined the impact of two group decision-making processes (decision rule and agenda) and one cognitive-motivational frame (aspiration level) on the quality of negotiated outcomes in small groups. Negotiation groups that used a unanimous decision rule were more likely to integrate their interests to achieve higher group outcomes than were groups that used a majority rule. Negotiation groups that followed an explicit agenda and used a majority decision rule distributed resources more unequally, and were more likely to form coalitions against a remaining party than were groups with no agenda/majority rule, explicit agenda/unanimity rule, and no agenda/unanimity rule. There was no support for the hypotheses that group members who held high aspirations and followed a majority decision rule would distribute resources more unequally than would groups with high aspirations/unanimity rule, low aspirations/majority rule, and low aspirations/unanimity rule; that adherence to explicit agendas would lead to lower group profits; and that the absence of high aspirations would lead to lower group profit. We discuss the results in terms of a mixed motive analysis of group decision making. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Majority and minority influence in group negotiation: The moderating effects of social motivation and decision rules.

In organizational groups, often a majority has aligned preferences that oppose those of a minority. Although such situations may give rise to majority coalitions that exclude the minority or to minorities blocking unfavorable agreements, structural and motivational factors may stimulate groups to engage in integrative negotiation, leading to collectively beneficial agreements. An experiment with 97 3-person groups was designed to test hypotheses about the interactions among decision rule, the majority's social motivation, and the minority's social motivation. Results showed that under unanimity rule, minority members block decisions, thus harming the group, but only when the minority has proself motivation. Under majority rule, majority members coalesce at the minority's expense, but only when the majority has a proself motivation. Implications for negotiation research and group decision making are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Negotiation in small groups.

The impact of issue agendas, decision rule, and power balance on the quality of negotiated agreements in small groups was examined. Three-person groups negotiated an agreement on three issues, with each issue having five alternative levels. Groups using sequential agendas were less likely to achieve mutually beneficial agreements than groups using package agendas. Groups following sequential agendas under majority rule achieved significantly less beneficial agreements than did groups following sequential agendas/unanimous rule, package agendas/majority rule, or package agendas/unanimous rule. As the predetermined alternatives to a negotiated agreement increased, so did individual profit. Results are discussed in terms of their implications for the quality of decision making in mixed-motive small groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Structural effects in simulated jury decision making.

Studied 28 12-person (17–56 yr old undergraduates) simulated juries to examine the effects of (a) a formally imposed decision rule (unanimity vs quorum) and (b) initial within-jury verdict preference distributions on group deliberation processes and decisions. Behavioral indicators were used to monitor the nature of group process under differing structural requirements while groups discussed either a more or a less ambiguous case. Compared with juries required to reach unanimity, juries required to obtain a quorum of 10 reached decisions twice as quickly and were much less likely to come to a stalemate resulting in a hung jury. Most important, these differences were due to the development of a different process from that which developed when juries were required to reach unanimity. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Choice shift and group polarization: An analysis of the status of arguments and social decision schemes.

Two Choice Dilemma Questionnaire items were used to investigate the influence of persuasive arguments and social decision schemes on group decisions. Furthermore, the predictions of the persuasive arguments theory on the polarization of individual preferences were tested. Ss were given lists of persuasive arguments and a 2nd individual decision was requested before the group discussion. The lists of persuasive arguments were compiled through a stepwise process of rating data gathered from the content analysis of former group discussions. In Condition 1, the Ss received the lists of arguments before the 1st individual decision; in Condition 2, between the 1st and 2nd individual measure; and in Condition 3 (control), they received no list at all. In all 3 conditions the reduced paired comparison median model showed the best fit and the highest hit rate in predicting the group decisions. The resulting choice shift could not be explained by the influence of arguments, whereas the best-fitting aggregation rule was able to clarify the choice shift. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Group and computer-mediated discussion effects in risk decision making.

Managers individually and in 3-person groups made multiattribute risk choices (two investment alternatives, each with multiple outcomes). Two group decisions were reached during face-to-face discussion, and two were reached during (real-time) computer-mediated discussion. In comparison with prediscussion individual preferences, groups' multiattribute risk choices and attitudes after face-to-face discussion were risk averse for gains and risk seeking for losses, a tendency predicted by prospect theory and consistent with choice shift and other group extremitization research. By contrast, group decisions during computer-mediated discussion did not shift in the direction of prospect theory predictions. The results are consistent with persuasive-arguments theory, in that computer-mediated discussion contained less argumentation than face-to-face discussion. Social decision schemes were used to evaluate alternative assumptions about the group process. A "(prospect-theory) norm-wins" decision scheme described group choice well in the face-to-face discussion condition, but not in the computer-mediated discussion condition. Another decision scheme, first-advocate wins, which described choices well in both face-to-face and computer-mediated discussions, was explored in a discussion of the role of communication in group decision making. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Information pooling: When it impacts group decision making.

Three-person groups decided which of 2 professors was nominated for a teaching award. Prior to discussion, half of the information available for this decision was given to every group member (shared information), whereas the rest was evenly divided among them (unshared information). Further, this information was distributed in such a way that the correct choice was not obvious to members prior to discussion. As predicted, discussion focused more on members' shared than unshared information. However, decision quality was affected only by the amount of unshared information discussed and by member's prediscussion choice preferences. The amount of shared information discussed did not affect decision quality. These results suggest a dual-process model of how the prediscussion distribution of decision-relevant information impacts group decision-making effectiveness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Discussion of shared and unshared information in decision-making groups.

Investigated the effects of task importance and group decision training on the discussion behavior of decision-making groups. 73 3-person groups decided which of 3 hypothetical faculty candidates would be the best person to teach an introductory psychology course. Prior to discussion, some of the information about each candidate was given to all group members (shared information), whereas the remainder was randomly divided among them (unshared information). Groups discussed much more of their shared information than their unshared information. Increasing the importance of the task slowed the rate at which information was brought forth during discussion. By contrast, group decision training increased the amount of both shared and unshared information discussed and altered the sequential flow of shared and unshared information into the discussion. Discussion in untrained groups focused first on shared information and then on unshared information; discussion in trained groups did not shift focus over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Group decision making in hidden profile situations: Dissent as a facilitator for decision quality.

The effect of diversity in individual prediscussion preferences on group decision quality was examined in an experiment in which 135 three-person groups worked on a personnel selection case with 4 alternatives. The information distribution among group members constituted a hidden profile (i.e., the correct solution was not identifiable on the basis of the members' individual information and could be detected only by pooling and integrating the members' unique information). Whereas groups with homogeneous suboptimal prediscussion preferences (no dissent) hardly ever solved the hidden profile, solution rates were significantly higher in groups with prediscussion dissent, even if none of these individual prediscussion preferences were correct. If dissent came from a proponent of the correct solution, solution rates were even higher than in dissent groups without such a proponent. The magnitude of dissent (i.e., minority dissent or full diversity of individual preferences) did not affect decision quality. The beneficial effect of dissent on group decision quality was mediated primarily by greater discussion intensity and to some extent also by less discussion bias in dissent groups. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Role of social loafing in predeliberation decision making.

The relationship between social loafing and decision making was examined in an individual predeliberation thinking task. Participants (N?=?189) were asked to read information and make decisions ostensibly in order to make a future individual or group decision. Decision type (intellective or judgmental) and anticipated group size (individuals or 4 or 8 members) were manipulated to examine their effect on information recall. Individuals who anticipated working alone or who believed they were making intellective decisions recalled more information than did those who anticipated working in groups or who believed they were making judgmental decisions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Judgmental subjectivity/objectivity and locus of choice in social comparison.

Two experiences were conducted to test the effects of judgmental subjectivity/objectivity on preferences of Ss to consult with like or unlike comparison partners. In Experiment 1, 101 Ss playing the role of admissions officers, were provided information about a college applicant and told either that the information was sufficient to allow for an objective decision on the candidate or that it was incomplete and, thus, that a subjective judgment was required. Objective-judgment Ss preferred dissimilar comparison partners. Subjective-judgment Ss preferred to compare with like others. Experiment 2, which involved a very different set of judgments (subjects played the role of jurors in a murder trial), replicated this finding and suggested that vested interest might influence Ss' motivation for comparison and comparison preferences. Implications of these results for a more precise understanding of social comparison were discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The group polarization phenomenon.

Experiments exploring the effects of group discussion on attitudes, jury decisions, ethical decisions, judgments, person perceptions, negotiations, and risk taking (other than the choice-dilemmas task) are generally consistent with a "group polarization" hypothesis, derived from the risky-shift literature. Recent attempts to explain the phenomenon fall mostly into 1 of 3 theoretical approaches: (a) group decision rules, especially majority rule (which is contradicted by available data); (b) interpersonal comparisons (for which there is mixed support); and (c) informational influence (for which there is strong support). A conceptual scheme is presented which integrates the latter 2 viewpoints and suggests how attitudes develop in a social context. (41/2 p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Pooling of unshared information in group decision making: Biased information sampling during discussion.

Studied 4-member decision-making groups given information about 3 hypothetical candidates for student body president in unshared/consensus or shared or unshared/conflict conditions. 84 undergraduates participated in the unshared consensus condition, and 72 undergraduates participated in the other conditions. Results show that even though groups could have produced unbiased composites of the candidates through discussion, they decided in favor of the candidate initially preferred by a plurality rather than the most favorable candidate. Group members' pre- and postdiscussion recall of candidate attributes indicated that discussion tended to perpetuate, not to correct, members' distorted pictures of the candidates. It is suggested that unstructured discussion in the face of a consensus requirement may fail as a means of combining unique informational resources. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Impact of a group decision on perception of one's own and others' attitudes.

We designed two experiments to examine the influence of a group decision on subjects' estimates of the attitudes of group members. In Experiment 1, subjects were led to believe that their initial vote in a jury decision-making task either agreed or disagreed with the majority vote and, independently of agreement with the majority, that their vote either agreed or disagreed with the final group decision. Subjects' own attitudes changed in the direction of the majority position only when the group decision was inconsistent with their initial vote. Consistent with prior research on the group attribution error, subjects inferred a correspondence between the final group decision and the other jurors' attitudes about the guilt or innocence of the defendant. In Experiment 2, subjects actively participated in or passively observed a group decision that either had or did not have direct consequences for the voting group. We found evidence of the group attribution error in both active participants' and passive observers' inferences about the attitudes of group members. Moreover, subjects tended to infer correspondence between the decision and the attitudes of voting members only when the decision had no immediate consequences for the group. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of group size and procedural influence on consensual judgments of quantity: The examples of damage awards and mock civil juries.

Six-person mock civil juries awarded significantly larger amounts for damages than did 12-person juries, and individuals preferred even larger average awards. A reversal of the "deep-pockets bias" observed earlier, an explanation involving temporal fluctuation in normative standards, during the time interval between the studies, was supported by independent data showing temporal trends in actual civil trial awards. A computational model of consensus that assumed a strong majority of those members with the most similar (closest) personal preferences decided on the median of their preferences accurately predicted award magnitude. Computer simulations explored the effects of critical faction size (majority, etc.) and location within the group, features that might in turn depend on task environment, cultural dynamics, and social context. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Knowing others' preferences degrades the quality of group decisions.

Results from 4 experiments demonstrate that learning the other group members' preferences at the beginning of a discussion impedes the solution of hidden profiles. In Experiments 1–3, participants who were not informed about their fellow group members' preferences were more likely to solve a hidden profile than those who received bogus information about the others' preferences. The negative effect of learning the others' preferences on decision quality was mediated by participants paying less attention to the information exchanged when they had been made aware of the others' preferences. Experiments 1 and 2 further ruled out that the effect of learning the others' preferences is due to participants bolstering their position or due to an increase in informational load. Experiment 3 showed that learning the other group members' preferences impedes the solution of hidden profiles even if one of the other members favors the correct alternative. Finally, Experiment 4 replicated these results in face-to-face interacting 3-person groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects on Decision Quality of Supporting Multi-attribute Evaluation in Groups

In this study the effectiveness of multi-attribute utility (MAU) decision support in groups is evaluated for personnel selection problems differing in complexity. Subjects were asked to make an initial individual decision with or without MAU decision support. Next individuals formed small groups and were asked to reach a decision about the same problem. Groups received either MAU support or no support. Results show that for relatively simple problems the most effective method is to provide subjects with both individual and group decision support. Here, decision support had a clear impact on subjects' preferences and the level of agreement between group members. In addition, satisfaction with the decision and the decision procedure was relatively high. Overall, decision support improved communication; subjects reported to find the problem easier, to have more influence on the group decision, and to find it easier to express their opinions. For more complex problems, however, decision making without group support (whether preceded by individual support or not) was evaluated most favorably. Individual decision support in this condition was sometimes better than no support; i.e., there was a lower reported problem difficulty, a higher satisfaction with the group decision, and a higher reported influence on the group decision. The effectiveness of group MAU decision support for complex problems was evaluated less favorably.