Determinants of support for group decisions

ORGANIZATIONAL

BEHAVIOR AND HUMAN

PERFORMANCE

22, 75-92 (1978)

Determinants of Support for Group Decisions CARL H . CASTORE

Purdue University AND J. K E I T H MURNIGHAN

University of Illinois The effects of three factors on the reactions of group members toward a group decision and the support they subsequently accorded such decisions were examined. These factors were: (a) the decision process used by the group (majority rule with formal voting, discussion to unanimity, discussion to majority agreement, or choice by an experimenter appointed executor); (b) the level of prediscussion agreement among group members (concordance); and (c) the relative extent to which an individual's preferences were congruent with his group's decision (relative individual goal attainment, RIGA). Individual ratings of satisfaction with decisions, anticipated commitment to decisions, and the support accorded to decisions were highest in groups with initially high concordance and among individuals higher on RIGA. Members of groups required to reach unanimity and those run by executive choice exhibited comparable support for their groups' decisions across all levels of concordance. In groups required to discuss to majority agreement, support of the group decisions dropped markedly under low levels of concordance. Individual ratings of the difficulty experienced in reaching a decision were highest in groups required to reach unanimous agreement. However, members of these groups showed the greatest degree of postdecision change in the direction of their groups' decisions.

The use of groups to make decisions is frequently motivated by the assumption that greater participation in the decision making process will lead to more effective implementation of whatever decision is eventually reached (cf. Lowin, 1968). However, a number of authors have suggested that participation in the decision making process, in and of itself, may not be sufficient to yield high levels of support for and satisfaction with the group decision in all circumstances (eg., Berrien, 1968; Castore, 1977; This research was supported in part by Grant No. GS-27711 from the National Science Foundation and in part by Contract N00014-67-A-0226 from the Office of Naval Research, Carl H. Castore Principal Investigator. The LP record albums used as subject payment were, in part, donated by A & M Records, the Atlantic Recording Company, and CBS Records; and, in part, purchased at special reduced rates from London Records, the Vanguard Recording Society, United Artists International, A B C - D u n h i l l Records, RCA Victor, Warner Brothers Reprise Records, and Capitol Records. Requests for reprints should be addressed to Carl H. Castore, Department of Psychological Sciences, Purdue University, West Lafayette, Indiana 49707. 75 0030-5073/78/0221 - 0075502.00/0 Copyright © 1978by AcademicPress, Inc. All rights of reproductionin any form reserved.

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CASTORE AND MURNIGHAN

Hackman & Morris, 1975; Thibaut & Kelley, 1959). Rather, these authors have suggested that the effectiveness of any particular decision process may be moderated by the overall diversity of group member predecision preferences and the subsequent congruence achieved between an individual's preferences and the group decision. Paradoxically, the experimental literature on groups has almost totally neglected the question of the extent to which such variables and other related factors might influence group member reactions to and implementation of decisions. Data from a scattering of empirical and anecdotal sources indicate that the use of majority rule in group decision making is a pervasive norm in American culture. Lewin, as early as 1936, had suggested that the general effectiveness shown by majority rule could be attributed to the increased participation and involvement by group members in the decision making process. More recently, Harnett (1967) found that individuals would only resort to a nonmajority process when majority rule could not resolve their conflict in a manner seen as equitable by all parties involved. At the same time, there are also a significant number of contexts in which other participative processes are seen as more effective or appropriate. For example, there is at present strong social pressure to continue the traditional requirement for unanimous jury decisions in criminal trials. There is typically an insistence on the use of Robert's Rules of Order in legislative bodies and in formal committee proceedings of all types. And, more centralized decision procedures in which a decision maker received information relevant to some choice from a variety of sources and then decides for the group as a whole are typical in the military, segments of the corporate world, and the governmental structure of numerous countries. On the other hand, normative decision theorists have generally regarded nonmajoritarian or nonparticipative decision processes as inequitable (Arrow, 1951; Black, 1957), and less accurate (Smoke & Zajonc, 1962). Further, such processes have been found to be relatively unproductive and, therefore, not promotive of support for group decisions or future interactions (Murnighan & Leung, 1976). The normative literature on group decision making (cf., particularly Black, 1957) suggests that diversity of group member preferences is a major limiting factor on the effectiveness of majoritarian decision processes. From a behavioral perspective Berrien (1968), Castore (1977), and Hackman and Morris (1975) all suggest that maximally effective group functioning is dependent upon a consensus among group members on group goal priorities and decisions related to these goals on both abstract and operational levels. The limited experimental data available (Castore, 1973; Harnett, 1967; Willerman, 1959) suggest that indeed simple majority rule cannot always resolve highly diverse preferences among group mere-

S U P P O R T FOR G R O U P DECISIONS

77

bers in a manner maximally conducive to subsequent effective group functioning. At the same time, there is little indication of the relative effectiveness of alternative decision procedures in such circumstances. Simple observation suggests that nations, organizations, and individuals frequently tend to exhibit more autocratic decision processes in such circumstances. However, whether this proclivity reflects any increased functional utility associated with these processes in such contexts, or simply the preferences of those with the greatest power at the moment cannot be readily ascertained. Both behaviorally oriented theorists (e.g., Berrien, 1968; Hackman & Morris, 1975; Thibaut & Kelley, 1959) and more normative theorists (eg., Coleman, 1966) concur that, regardless of the decision process, individuals whose preferences are in closer accord with a group's decision will be more supportive of that decision. Indeed, Coleman and others suggest that this factor should logically be the primary determinant of the support an individual would give to a group decision given a situation in which the group could not exert coercive pressure on the individual. Two previous studies by Castore (1973, in press) found that, within groups, individual reactions to and support of majority rule decisions were closely related to, although not totally determined by, the relative agreement between a person's preferences and the decision reached by his group. However, the extent to which this factor functions independently of the decision process used in a group as a determinant of group member reactions to group decisions is far from clear. The present study was undertaken then to determine the extent to which the diversity of group member preferences and the congruence between individual preferences and their group's decision affect individual's reactions to group decisions and their subsequent support of such decisions under various social decision schemes.

METHOD

Design. The study used a 5 x 5 x 4 between-groups factorial design in which the factors were, respectively, the level of preference agreement among the group members (concordance); the relative congruence between a group member's preferences and the group's decision (relative individual goal attainment, RIGA); and the decision process used by the group. Groups were designated as high, moderately high, moderate, moderately low, or low concordance on the basis of the calculated concordance among group members' rankings of alternative goals, Kendall's W (Kendall, 1943). Groups for which W ~ .00 were designated as low concordance; those for which W ~ .20, moderately low concordance; those for

78

CP~STORE AND MURNIGHAN

which W --- .40, moderate concordance; those for which W --- .60, moderately high concordance; and those for which W --- .80, high concordance. 1 The five individuals within each group were assigned to one of the five levels of RIGA (greatest through least) on the basis of the magnitude of the rank order correlation (Spearman's p) between their initial, prediscussion, ranking of the alternatives and their group's ranking of the alternatives. The four different decision processes used by the groups were: (a) majority rule with parliamentary voting; (b) discussion to majority agreement; (c) executive choice; and (d) unanimity. Groups in the majority rule with parliamentary voting condition were told to begin by chosing any pair of alternatives and, after any discussion desired, to vote between them. The winning alternative (that one obtaining at least three out of the five votes) was to be paired with one of the remaining alternatives and the process would be repeated. Sequential pairings of this nature were continued until one of the alternatives remained as the group's first choice. The remaining alternatives were to be similarly selected, discussed if desired, and voted upon until the second, third, fourth, and fifth choices had been determined. Groups in the discussion to majority agreement condition were simply told to reach a decision about the ranking of the alternatives in which at least a majority of the members concurred. Groups in the unanimity condition were told that they should discuss their preferences until they all agreed upon the ranking. The experimenters emphasized that any group member could keep the discussion open until he agreed with the decision. One member of the groups in the executive choice condition was randomly designated by the experimenter as the "decision maker" (executive) for the group. The other group members were told that they could present arguments in favor of their own personal preferences, but that the final decision for the group would be made solely by the decision maker. Subjects. The members of the 40 five-person groups (two groups at each concordance level under each decision process) used in this study were 200 male volunteers enrolled in introductory psychology classes at There were two groups at each level of concordance under each decision rule. The mean concordance values for each pair of groups under each decision rule were: Majority rule with Parliamentary voting Majority consensus Unanimity Executive choice

.10, .13, .07, .05,

.21, .20, .24, .24,

.31, .38, .39, .40,

.55, .58, .61, .61,

and and and and

.80 .81 .80 .81

An attempt was made to have concordance in the low agreement condition equal approximately .00 for all groups. However, due to somewhat restricted variability in the subjects' preferences, it was impossible to attain this level in practice.

SUPPORT

FOR GROUP DECISIONS

79

Purdue University. All participants appeared in response to an advertisement which promised a free 33½ LP record album and credit toward a course requirement for participating in the study. It was made clear to all participants prior to their volunteering that the exact LP album they would receive would depend in large part upon the decisions reached by their particular group. Task. Two tasks were required of each participant. The first task was chosen to simulate conditions that exist when individuals must reconcile conflicting preferences to reach a group decision. This task required the group members to rank order a set of five LP record albums using the decision processes assigned to their group. All groups were given as much time as they required to arrive at this group ranking. The participants were informed that the group ranking would, in part, determine the LP album each of them would receive, as follows: The group ranking would be used to establish a lottery such that the first choice of the group would have a 35% chance of being the album each would receive; the second choice, a 30% chance; the third choice, a 20% chance; the fourth choice, a 15% chance; and the fifth choice had no chance of being selected. Effectively, the album which was ranked first received 35 chips in the lottery; that ranked second, 30 chips; that ranked third, 20 chips; that ranked fourth, 15 chips; and that ranked fifth, 0 chips. As a reminder to the participants, these probabilities and the number of chips that would go into the lottery in each case were noted on a blackboard in the room where the discussions were held. Following the group ranking of the LP albums, each group member completed four scales (0-100 graphic rating scales) describing his reactions to the group decision in terms of (a) how satisfied he personally was with the group ranking; (b) how fairly he thought it represented the preferences of the group as a whole; (c) how committed he would be to the group decision if he had to defend it; and (d) the degree of difficulty he felt his group had experienced in reaching it. In addition, the subjects also indicated the proportion of influence they thought each member of their group, including themselves, had exerted on the group decision. (This latter question formed the basis for two variables in the analyses: (a) the average amount of influence on the group decision attributed to an individual by his fellow group members and (b) the amount of influence an individual saw himself as having in the group decision process.) After completing these measures, the subjects completed a scaling task (Siegel, 1956). In its simplest form these data provided an indication of a subject's ranking of the alternatives following the group discussion and decision. A comparison of this ranking with that obtained just prior to the group interaction was used to provide an indication of preference changes as a result of the discussion-decision process.

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CASTORE AND M U R N I G H A N

The second portion of the experiment was a bargaining situation which permitted a behaviorally based assessment of an individual's support of his group's position with minimal potential for coercive pressures from other group members. In this task, each group member met with a member from another group that had been present at the same time, in another room, and which had also ranked (differently) the same set of five LP albums. Each of these five dyads was given the task of negotiating the discrepancies between the groups' decisions to arrive at another joint ranking of the LP albums. Members of each dyad were informed that the negotiated first choice of each dyad would receive an additional seven chips in each of their groups' lotteries; the second choice, six additional chips; the third choice, four additional chips; the fourth choice, three additional chips; and the fifth choice, no additional chips. An individual's support for his group's decision was assessed in terms of the correlation between the ranking negotiated in the bargaining dyad with the member of the other group and his own group's ranking. Procedures. All subjects ranked several sets of five LP albums 1 week prior to their participation in the experiment. These rankings provided the preliminary basis of scheduling participants into groups. Preference rankings of the particular set of albums to be used in an experimental session were also obtained from the participants upon their arrival. To maintain appropriate concordance levels, subjects whose preferences had changed were assigned, if necessary, to different groups. Thus, the concordance levels of the groups in each condition reflected their members' preferences immediately prior to the group discussions. The group decision task and the first stage of the lottery were then explained to the participants and any questions were answered. Discussions were begun only after it was clear that all group members clearly understood the operation of their assigned decision process and the way their decision determined the lottery. After the group decision, the group members completed the various ratings and the scaling task. The negotiations task and the overall lottery were then explained to the members of both groups. In this phase of the experiment, the subjects in each dyad were instructed to negotiate a mutually acceptable ranking of the record albums. Each subject was given a form with his group' s ranking indicated which contained blank spaces in which he could record the dyad's negotiated ranking. Since individuals were not constrained to accurately present their group's decision during the negotiations, they could choose to operate in either their own or their group's interest in so far as they deemed appropriate. If there were any questions from the subjects about whether they were to act in their own interest or to act only as representatives of their groups, the experimenters simply reiterated that their task in their dyad w.as to arrive at a mutually acceptable ranking. Following these

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instructions, the individuals were randomly assigned to dyads and these dyads were placed in separate rooms to conduct the negotiations. Following the negotiations task, the lotteries were constructed and drawings were held to determine the LP album received by the members of each group.

RESULTS Eight dependent variables were considered within the framework of the present study. Four of these variables were derived from the subjects' responses on the 100-point graphic rating scales: (a) satisfaction with the group decision; (b) commitment to the group decision; (c) difficulty in reaching the group decision; (d) the extent to which the group decision was a fair representation of the group members' preferences (representativeness). Two of the variables were measures of the proportion of influence on the decision process attributed to a group member (e) by himself and (f) by the other members of his group. The seventh measure in the analysis (g) was the extent to which an individual changed his preferences in the direction of his group' s decision. This was calculated as a proportion of possible preference change:

Percentage preference change =

(final - i n i t i a l ) x 100 1.00 - initial

where "final" is the Spearman rank correlation between an individual's preference ranking at the end of the session and his group's decision, and "initial" is the corresponding correlation for an individual's preferences prior to the group discussion. The eighth variable in the analysis (h) was the aforementioned measure of behavioral support for the group decision, calculated as the correlation between the ranking an individual negotiated in the bargaining dyad and the ranking which was his group's decision. The overall intercorrelations for these eight variables are found in Table 1. Each dependent variable was analyzed in a separate 4 (decision rules) x 5 (concordance) x 5 (RIGA) analysis of variance. The means associated with the significant main effects found for each variable are indicated in Table 2. Differences between means associated with significant main effects were tested by means of planned comparison procedures (Winer, 1962). The results of these tests are indicated by subscripts within Table 2. In all eight analyses, only one significant interaction was found, that for the effects of decision rules and concordance on the behavioral support given the group decision. The means associated with this interaction are found in Table 3. Differences between means, indicated by subscripts in the table, were examined by means of planned comparison procedures. A final portion of the analysis was directed toward an examination of

Mean SD

Decision rule Concordance RIGA Commitment Difficulty Satisfaction Representativeness Influence/own Influence/associates Behavioral support

Variable

-.0t

Conco~ dance

.00 .00

.28 -.20 .00 -.23

22.7 21.4

76.5 18.5

Difficulty

.15 .25 -.33

Decision rule C o m m i t m e n t

76.4 23.1

.04 .26 -.36 ,70 -.25

Satisfaction

80.5 16.9

-.13 .14 -,13 .40 -.35 .56

Representativeness

.00 .01 -.07 .05 .02 .06 .03 .55

8.3 6.0

.00 .00 -,05 ,13 -,03 .09 .06

20.0 2.2

Influence/ Influence/ own associates

TABLE 1 INTERCORRELATIONS, MEANS, AND STANDARD DEVIATIONS AMONG THE VARIABLES ACROSS ALL LEVELS OF CONCORDANCE AND OVER ALL DECISION CONDITIONS

.68 .29

- . 10 .32 -.12 .28 -,30 .32 .21 .12 - .02

Behavioral support

32 7.8

.19

-.06

.15 .ll .28 .10 .02 .17 .12 .00

Percentage preference .... _change

Z

O

f3

t~

OO

SUPPORT FOR GROUP DECISIONS

83

the extent to which the decisions arrived at by the groups under the various decision rules were comparable to that which would be predicted by the application of a majority rule decision model to the group members' preferences prior to the group decision (cf. Davis, 1973). The formal model considered was one which considered all possible pairings of the alternatives to arrive at an expected group decision. Spearman rank order correlations were computed between the decision a group actually reached and that decision predicted by the formal majority rule model. These correlations were analyzed in a 4 (decision rules) × 5 (concordance) factorial analysis of variance. Since groups were the unit of analysis in this instance, there was only an n of 2 per cell, greatly reducing the power of the test. Nonetheless, a significant main effect was noted for concordance (F (4,20) =- 3.70, p < .05). The main effect for decision rules and the interaction effect were not significant (F < 1.00 in each instance). Post hoc comparisons among the means at each level of concordance indicated significantly less correspondence between the formal majority rule model's predictionsat low concordance ()( = .42) than in the high concordance condition (X = .92). The values for the other levels of concordance, falling between these two extremes, were not significantly different from one another.

DISCUSSION From the overall pattern of results obtained in the present study, it is clear that group member reactions to any particular decision process and the subsequent effectiveness of that process, as measured by support engendered, were strongly affected by the overall level of diversity of preference found within a group. Indeed, the overall pattern of results indicated that such diversity (concordance) was generally more important than the particular decision process used in determining member reactions to group decisions. Also, within a group, reactions to a group decision were further moderated by the relative (rather than absolute) degree of correspondence between the decision reached by the group and the preferences of the individual group members. And, with the exception of the findings for behavioral support, the effects of the three factors considered on reactions to group decision were largely independent. Decision Rules When the decision processes examined in the present study are ordered in terms of the amount of discussion each engendered, the results noted for rated commitment, rated difficulty, and percentage preference change were in general accord with what would be anticipated from the literature on the effects of participation in the decision process (e.g., Lowin, 1968). The greatest amount of interaction was found in the groups required to reach unanimous decisions, while the next greatest amount of discussion

Decision rules Majority rule with formal voting Executive choice Unamimity Discussion to majority a g r e e m e n t F(df = 3,100) p 15.4,7 21.7b 34.0~ 18.9 b 6.40 <.01

79.0 a 2.90 <.05

Difficulty

70.9b 77.4a 79. I a

Commitment

< 1.00 n.s.

Satisfaction

< 1.00 n.s.

Representativeness

< 1.00 n.s.

Influence/ own

D e p e n d e n t variable

< 1.00 n.s.

Influence/ associates

29.0a 2.62 <.055

26.8a 27.2a 43.8b

Percentage preference change

WHICH RESULTED IN A SIGNIFICANT MAIN EFFECT FOR DECISION RULE, CONCORDANCE, AND RIGA"

TABLE 2 A SUMMARY OF THE ANALYSES AND THE MEANS FOR EACH DEPENDENT VARIABLE

.730~b 9.92 <.01

.806a .558~ .662~,

Behavioral support

OO

21.7b~ t 2.4~

8 0 . 5 ab

84.6a 6.07 <.01

79. lab 81.4a 71. lb~ 63.0~ 8.94 .01

79.3ab

76.4b

75.3b 66.3° 7.72 <.01 <

87.5a

7.17 <.01

86.5~

83.0~

74,3hc 64.90 73.5cd

85.9a

< 1.00 n,s.

4.68 <.01

21.5bc 34.2 a 22.7 b

74.(~o~ 68.2~ 75.7b

< 1.00 n.s.

84.3a 4.65 <.01

82.4~

81.6a 70. Ib 83.6a

18.7.b 16.6b 2.27 <.07

22.8a

19.3.b

21.7a

< 1,00 n.s.

19.2b~ 18.5~ 2.74 <.05

22.2~

19.5abe

21.6,b

< 1.0O n.s.

42.1 40.5~ 4.84 <.01

38.5ab

22.9be

14.3~.

< 1.00 n.s.

.677ab .632b 1.43 b .25

•687a0

.690ab

.757 a

.630b .512~ .715b .710b .877 a 12.75 <.01

~' Cells sharing a common subscript, within the levels of each dependent variable, are n o t significantly different from one another at the .05 level using the planned comparisons procedure (Winer, 1962). b Because of the theoretical interest in these two variables, planned comparisons were carried out in the absence of a significant main effect.

RIGA Most similar Second most similar Third most similar Fourth most similar Least similar F(4,100) p

F(4,100) p

•4 0 - . 5 9 •6 0 - . 7 9 •8 0 - 1 . 0 0

Concordance .00-.59 .20-.39

G,O

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CASTORE AND MURNIGHAN

TABLE 3 A SUMMARY OF THE ANALYSES AND THE MEANS FOR THE SIGNIFICANT (F(12,100) = 4.73, p < .01) INTERACTION BETWEEN DECISION RULE AND CONCORDANCE FOR BEHAVIORAL SUPPORT c'

Decision rule Majority rule with formal voting Executive choice Unanimity Discussionmajority agreement

Concordance .00-. 19

.20-.39

.40-.59

.60-.79

.80-1.00

.820ab

F

p

2.21

<. 10

.780ab

.850a

.700b

.880a

.570b .730b

.160c .360c

.660ab .680b

.600ab .540be

.800a 1.00a

8.99 7.03

< .01 <.01

.440¢

.680b

.820ab

.820~b

.890a

6.81

<.01

Cells sharing a common subscript within each decision are n o t significantly different from one another at the .05 level using the planned comparisons procedure (Winer, 1962). b The F values were calculated for each decision rule separately. Degrees of freedom in each case were 4 and 45. took place in the groups required to discuss the choices until at least a majority of the group was in agreement. There was at least a m o d e r a t e a m o u n t of discussion guaranteed in the executive choice condition. All group m e m b e r s could present their preferences and their rationale to w h a t e v e r extent they desired. On the other hand, only minimal discussion was n e c e s s a r y in the groups operating bY majority rule with parliamentary voting. The group m e m b e r s only had to choose the pairs of alternatives to be considered. The p r e s e n c e of an odd n u m b e r of group m e m b e r s insured that a majority choice (3:2, 4:1, or 5:0) would result for each pair of alternatives considered. Accordingly, this condition engendered very little discussion in the f o r m of arguments for positions and persuasive attempts. T h a t discussion which did emerge tended to focus primarily on procedural matters. The ratings of the difficulty experienced in reaching decisions were generally a reflection of the a m o u n t of time it took to reach a g r e e m e n t u n d e r the different decision p r o c e d u r e s . It t o o k groups considerably longer to r e a c h unanimous a g r e e m e n t than to resolve their conflicting preferences by any of the other procedures. (It should be noted that, although the majority rule condition with formal voting did not engender m u c h discussion, it still required a m o d e r a t e a m o u n t of time to determine the complete ordering of alternatives by the required series of pairwise comparisons.) At the same time, it would a p p e a r that ratings of anticipated c o m m i t m e n t were highest in those conditions which gave the par-

SUPPORT FOR GROUP DECISIONS

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ticipants an equal chance to explicate their position. This aspect of the findings parallels the recent findings of Houlder, La Tour, Walker, and Thibaut (1978) for the impact of an equitable distribution of process control over an adjucative conflict resolution situation. In contrast, the behavioral support was greatest in those conditions which provided the most equitable distribution of control over the decision making among group members. In the executive choice condition, one person the experimenter appointed decision maker had the final authority to make the group's choice. And, in the unanimity condition, any individual who felt strongly enough about the outcome could exert a disproportionate impact on the outcome by withholding his approval until he was satisfied. The finding of no differences in the ratings of personal satisfaction with the decisions and the representativeness of them across the different decision procedures would appear attributable to the fact that the decisions were, indeed, equally mathematically representative (and hence as "fair" as obtainable) across the different required decision procedures. The greatest degree of preference change was found in the unanimity condition--that which required the greatest amount of discussion. At the same time, the unanimity condition produced significantly less behavioral support for the group decisions than either of the two majority rule conditions, most particularly in the moderately low, moderate, and moderately high concordance conditions (cf. Table 3). There are two readily apparent reasons which individually or in combination suggest themselves as possible explanations for this apparent contradiction. First, preference change was measured prior to the situation in which behavioral support was assessed. It may have been that the apparent preference change was not particularly stable in the face of contradictory pressures with no immediate support. This would seem particularly likely in those cases in which the other group's position might have been somewhat closer to a subject's initial position than that decided upon by his own group. This discrepancy may also reflect the possibility that an equitable distribution of participant control over the process by which views were presented was not sufficient to engender subsequent behavioral support for decisions reached in the absence of a corresponding equitable distribution of participant control over the actual decision making. Concordance

As anticipated, the greater the prediscussion agreement within the group, the more the participants were favorably disposed toward, and supportive of, the decisions reached. Indeed, the impact of concordance was generally linear from moderately low through high concordance on ratings and/or perceptions of anticipated commitment, difficulty in reaching a decision, personal satisfaction, representativeness of the group decision,

88

CASTORE AND M U R N I G H A N

and subsequent behavioral support. Paradoxically, ratings of anticipated commitment, satisfaction with the group decision, the representativeness of the decision, and the subsequent support accorded the decision were all greater at low concordance than at moderately low concordance. And, in the same vein decisions under low concordance were seen as easier to reach than those under moderately low concordance. This pattern is particularly intriguing in view of the fact that the decisions of low concordance groups were less representative, mathematically, of group member preferences than those reached at the other concordance levels. One possible explanation of this apparent contradiction is suggested by the works of Alger (1973), Castore (1977), and Cummings, O'Connell, and Huber (1977). These authors have suggested that, at higher levels of disagreement within a group, discussion or explication of positions may only serve to underscore potentially divisive differences among various positions and precipitate movement of group members into opposing coalitions. The present data suggest that this may occur at the moderately low and moderate levels of concordance, but not at the lowest levels. Although the explication of positions at low concordance would emphasize the differences, it would also highlight the fact that no coalition would be any more advantageous than any other to a particular group member. And that, in effect, all positions would have to be compromised equally to reach any agreement. Thus, such decisions would have an aura of equity associated with them, but for different reasons than at other concordance levels. The significant interaction between concordance and decision rules on behavioral support, indicated in Table 3, is a reflection of many of the points noted in the examination of the main effects for each of these factors. The relatively uniform level of support noted for decisions reached under majority rule with formal voting would appear to reflect: (a) the cultural norm of fairness associated with this procedure, as noted by Harnett (1967), and (b) the relative ignorance of others' positions arising from the lack of other than procedural discussions in this condition. Without information about the exact nature of others' preferences, the individual would have no basis for determining how well he had fared, relative to the others in his group, as a result of the group decision. Indeed, as reflected in analyses of the ratings of satisfaction, representativeness, and influence within this condition (no significant main effects or interactions), the individuals could only assume that the decisions were "fair" and that they had done as well as the others in their group and that each had an equal impact on the outcome. In contrast, behavioral support for group decisions reached under the requirement of discussion to majority agreement decreased steadily with lower levels of concordance. The decisions reached in this condition were

SUPPORT

FOR GROUP

DECISIONS

89

no less representative, mathematically, of group member preferences than those reached in the groups operating with the requirement of majority rule with formal voting. Both conditions afforded individuals equitable control over the decision making. The primary difference between these two conditions was that, under discussion to majority agreement, the subjects were all aware of the preferences of the other group members. Accordingly, there was more opportunity for the divisive effects of discussion to operate at the lower concordance levels. To a lesser extent (note the marginally significant effect for RIGA on behavioral support) such a knowledge would facilitate potentially disquieting comparisons of the relative satisfactoriness of outcomes among group members. Subjects in the executive choice condition, as noted, had equitable process control, and the group decisions were mathematically as equitable as those reached in the other three conditions. There was a sharp drop in the level of support observed here as concordance decreased from high through moderately low. When contrasted with the results from the discussion to majority agreement condition, this would appear to reflect the difference in reactions to a process having both equitably distributed process and decision control (discussion to majority agreement) and reactions to a process with only equitably distributed process control (executive choice). The same can be said for the differences between the unanimity and the discussion to majority agreement condition. When the range of concordance from high through moderately low is considered the data would suggest that, in contrast to the conclusions of Houlder et al. (1978), equitably distributed process control is not as important as equitably distributed decision control in determining reactions to and support of group decisions. However, a careful examination of the procedures of Houlder et al. suggest that their conflict situation was more akin to the low concordance condition of the present study than any other. And, the results in this condition, with both unanimity and executive choice engendering greater support than discussion to majority agreement, are in general accord with their findings. This in turn suggests that a condition of total disagreement among group members is in some ways disjunctive from all higher levels of concordance. Relative Individual Goal A t t a i n m e n t (RIGA)

As anticipated from the theoretical positions of Thibaut and Kelley (1959), Berrien (1968), and Hackman and Morris (1975), the degree of congruence between an individual's predecision preferences and his group's decision (RIGA) was found to be a significant determinant of individual reactions to group decisions. In general, the greater the degree of such congruence, the greater the anticipated commitment, satisfaction with, and subsequent support of the group decision. Also, individuals

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higher on RIGA saw themselves and were seen by the others in their group as being more influential in the decision process. Conversely, those individuals lowest on RIGA showed the greatest apparent preference change in the direction of the group decision. The apparent contradiction between the degree of preference change and behavioral support would appear, as in the case of the similar contradictory findings for decision rules, to be attributable to the possibility that such apparent changes might be relatively unstable in the face of subsequent contradictory pressures with no immediate support. In sum, it would appear that merely having individuals present their views and having them share equally in the decision making is not sufficient to insure that all of the participants will be equally favorable toward and supportive of a group decision. The effectiveness of decision processes is moderated by both the overall diversity of group member predecision preferences and by the relative congruence between an individual's preferences and his group's decision. Overall, the most effective decision process (in terms of support generated) would appear to be one which would not reveal the exact nature of group members' preferences to each other, while giving each equal control over the actual decision making. Such a procedure would seem to be rarely attainable in practice, as most parties to a decision are aware (or become aware) of the nature of the other participants' preferences. At high levels of concordance, the decision process used would seem to be of little consequence. At moderate levels of concordance, the most effective decision procedures are those which permit the individuals to exert equal control over the decision reaches. In contrast, at the lowest level of concordance the most effective decision processes are those which allow for an equal control over the explication of positions, but not necessarily over the actual decision making. Within groups, individuals appear to support group decisions to the extent that they are in accord with their own preferences, regardless of how such decisions are reached. Finally, in this vein it is particularly interesting to note that unanimity, a decision process frequently viewed as optimum (cf. Lowin, 1968), is only effective at very high and very low concordance levels. At all other levels, unanimity appears, from the present data, to generate much less support than majoritarian processes, despite the essential equivalence of the decisions reached. The requirement for unanimity does indeed appear to create a situation which, as suggested by Sir Francis Galton (1910), "gives power to cranks in proportion to their crankiness," rendering it a potential dictatorship of the most concerned group member(s). While this limitation does not appear to be too bothersome when all in a group are i~ relatively high accord, or when there is total discord, at all other levels

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compliance with decisions reached appears to be primarily determined by initial agreement with the "dictator(s)" in the group. Finally, it should be noted that the present research was concerned with the making and carrying out of a single decision. It remains to be seen the extent to which the observed processes, as well as additional temporal factors, operate in ongoing groups which make and carry out a number of decisions over time.

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