The effects of alternatives in bargaining

JOURNAL

OF

EXPERIMENTAL

SOCIAL

PSYCHOLOGY

15,

The Effects of Alternatives

147-157 (1979)

in Bargaining

S. S. KOMORITA AND DAVID A. KRAVITZ University of Illinois Received February 28. 1978 Research in bargaining situations has shown that the outcomes obtained by the parties if agreement cannot be reached have significant effects on the nature of the agreement. However, no previous study has attempted to determine the precise nature of the relationship between such alternative outcomes and bargaining agreements. Groups of 2, 3, and 4 undergraduate males were asked to negotiate the division of five prizes under two distributions of alternatives, and the predictions of three norms of reward division were compared. The Equal Excess norm specifies that each member receives the value of his alternative and that the excess (prize less sum of alternatives) is equally divided. This norm provided the best description of the data, but systematic errors of prediction were observed. The implications of the results for theories of coalition formation and for equity theory are discussed.

A critical variable in bargaining and negotiation is the nature of the alternative outcomes available to the parties if an agreement cannot be reached. In union-management negotiations for example, if the union threatens to strike, it may force the company to choose between an unfavorable labor contract (make concessions) and a costly shutdown of the plant (the alternative). Thus, the party with the poorer (more costly) alternative can be expected to make relatively large concessions. According to Thibaut and Kelley’s (1959) exchange theory of social interaction, the relationship between power and alternatives is specified by the concept of “comparison level for alternatives” (CL&), defined as ‘. . . . the lowest level of outcomes a member will accept in the light of available alternative opportunities” (p. 21). According to this conceptualization, Person A’s power over Person B is inversely related to Person B’S CLalt; the greater Person B’s CL&t, the less power A has over him.’ This study was supported in part by a research grant from the National Science Foundation (BNS 77-09542) to the first author. Portions of the paper were presented at the meetings of the Society,of Experimental Social Psychology, October 1977, in Austin, Texas. Send reprint requests to Dr. Samuel Komorita, Department of Psychology, University of Illinois, Champaign, IL 61820. ’ Komorita (1977) has extended Thibaut and Kelley’s conceptualization of social power to distinguish between bargaining power and “tactical advantages” achieved during the course of bargaining. In this paper we shall only be concerned with actual bargaining power. In addition, several bases of power have been postulated by French and Raven (1959), but for the purpose of this study we shall restrict ourselves to “reward” and “coercive” power. 147

0022-1031/79/020147-11$02.00/O Copyright @ 1979 by Academic Press, Inc. All rights of reproduction in any form reserved.

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Thus, each person’s CL&t sets a lower bound on the bargaining range of outcomes. For example, in a buyer-seller relationship, a seller who has an offer of $X from another buyer is not likely to concede below $X in the negotiations. There is some direct empirical support for this conceptualization of power from studies in two-person bargaining and from studies of coalition formation. Yukl (1976), for example, manipulated the alternatives of buyer and seller in a bargaining situation and found that the agreement price was higher when the alternatives favored the seller than when the alternatives favored the buyer. Similarly, in a three-person coalition experiment, Kelley and Arrowood (1960) varied the alternatives of the three players and found a direct relationship between the alternatives of the players and their respective shares of the prize. There are additional studies that provide indirect support for the effects of alternatives in bargaining, but we shall not review them here (cf. Thibaut & Faucheux, 1965; Pruitt & Drews, 1969; Komorita & Barnes, 1969; Rubin & DiMatteo, 1972; Lawler & Bararach, 1976). AN EQUAL EXCESS NORM OF REWARD DIVISION

Despite the empirical evidence concerning the importance of alternatives in bargaining, there have been few attempts (if any) to determine the precise effects of such alternatives on the distribution of rewards to the bargainers. The relationship between alternatives and reward allocation is an important research problem not only for bargaining theory, but also for theory and research in coalition formation and for equity theory. Accordingly, the main purpose of this study was to test the validity of a plausible hypothesis (norm) regarding reward division; this hypothesis will be called the Equal Excess norm. If we let V denote the value of the prize to be divided and let Sr denote the share of V for individual i, the Equal Excess norm is defined as follows: Si = Ai + i

(V - iA&,j

= 1, 2, 3, . . ., n

(1)

where Ai denotes the alternative of individual i, and IZ denotes the number of bargainers. The Equal Excess norm specifies that each person should receive his (her) alternative (Ai) and that the excess, (V - IZAJ, should be divided equally among the bargainers. Under the assumption that the payoffs represent the utilities of the bargainers, it can be shown that the Equal Excess norm is a derivation of Nash’s solution (1950, 1953) to the general bargaining problem, and Nash has shown that his solution maximizes the product of the utility increments (Si - A,) of the bargainers. For example, consider a situation in which two persons are asked to

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bargain over the division of 100 points (V = 100). If they cannot reach agreement over the division of the prize, Person 1 receives an alternative prize of 40 points (A, = 40), while Person 2 receives 20 points (A2 = 20). Substituting these values in Equation 1, we have: S1 = 40 + (l/2)( 100 - 60) = 60; and S2 = 20 + (l/2)( 100 - 60) = 40.2 It can be shown that there is a relationship between the Equal Excess norm and two other possible norms: The Proportionality norm, which specifies that a person’s share should be directly proportional to the value of his (her) alternative, and the Equality norm, which specifies that alternatives are irrelevant and all shares should be equal. Although these norms may appear implausible, there are precedents for the principles underlying them in the equity literature, if one assumes alternatives are equivalent to inputs (cf. Adams, 1965; Walster, Berscheid, & Walster, 1973), and in the coalition literature (cf. Gamson, 1964; Komorita & Chertkoff, 1973). In the previous example, the Proportionality norm predicts a 67-33 split for Persons 1 and 2, respectively (proportional to alternatives of 40 and 20), while the Equality norm predicts an equal split (50-50). In terms of the proportional share of V for individual i, as V becomes indefinitely large (V+m), it can be shown that the predictions of the Equal Excess norm converge to those of the Equality norm (l/n). Similarly, as V approaches the sum of alternatives of the bargainers, it can be shown that the Equal Excess and Proportionality norms make identical predictions. These relationships between the Equal Excess norm and the two other norms suggest that the value of the prize (V) is an important variable in contrasting the predictions of the three norms. In terms of the proportional share of the prize for the bargainers (Pi), the predictions of the Proportionality and Equality norms are invariant over prize values, but the Equal Excess norm predicts that Pt should vary with the magnitude of the prize. In addition to prize value, it was hypothesized that the validity of the three norms might also vary with two other variables: group size, and the distribution of the alternatives of the bargainers (both are factors in Equation 1). Hence, three variables were manipulated in the study: prize value (V), group size (n), and distribution of alternatives &). METHOD Subjects The subjects were 126 male undergraduates enrolled in introductory psychology classes. Participation in the experiment partially fulfilled a course requirement. Three additional subjects (one triad) were dropped from the experiment for not following instructions. * When the alternatives of the parties are specified, as in this example, it can be shown that the Nash solution (1950, 1953) and the Shapley value (1953) make identical predictions. Moreover, in a coalition situation, it can be shown that the equal excess norm is a derivation of Aumann and Maschler’s Bargaining Set (1964).

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Procedure Subjects were scheduled in groups of 2, 3, or 4 persons, depending on the group size condition, and were seated in classroom desks facing each other. Subjects were informed: (a) that they would be asked to bargain among themselves over the division of a prize consisting of a given number of points; (b) that there would be many sessions (trials) in the experiment; (c) that in each session they would be allowed either to divide the prize, through face-to-face bargaining, or to receive an alternative number of points if they could not reach agreement; and (d) that unanimous agreement would be required, so if one person decided to choose his alternative, all of them must take their alternatives. The stimuli (combinations of prize value and alternative) were presented in a booklet with one stimulus per page. Two blank pages were inserted at the end of the booklet so the subjects would not know when they were bargaining for the last time. A stimulus page consisted of a prize value (V); the alternative of each person in the group (A*); and blank spaces to indicate the negotiated shares of each person, if an agreement was reached. Each subject had a copy of the booklet, but only one booklet was filled in by each group. One subject was randomly assigned the task of indicating whether agreement had been reached, and of entering the point division in the space provided on each page. All persons were asked to initial each page of the booklet after each trial. They were asked to complete the pages in the order presented in the booklet and not to turn back to a page after it had been completed. In addition to group size, distribution of alternatives and prize value were varied. Two distributions of alternatives were used. In both distributions there was a single “strong” person, denoted Person S, whose alternative was always greater than the alternatives of the other member(s) of the group. In one condition, the alternative of Person S was twice as large as the sum of the alternatives of the weaker person(s), while in the second condition the alternative of Person S was five times as large. We shall refer to these two conditions as “power ratios” of 2:l and 5:1, respectively. Table I shows the distribution of alternatives for Person S and the weaker member(s) of the group for the two distributions. It can be seen that the alternatives of the group members always summed to 36, and for each level of power ratio the alternative of Person S was constant across group size. These restrictions on the distribution of alternatives constrain the ratio of Person S’s alternative to the sum of alternatives to be constant across group size. Since the Proportionality norm predicts that Person S’s proportional share of the prize should be equal to the ratio of his alternative to the sum of alternatives, the Proportionality norm predicts that Person S’s proportional share of the prize will be constant across group size. The Equal Excess norm, on the other hand, predicts that Person S’s share will be inversely related to group size (see Equation 1). Obviously, the Equality norm also predicts an inverse relationship between Person S’s share and group size. Hence, these restrictions provide a critical comparison of the three norms: The Equal Excess and Equality norms predict that Persons S’s proportional share should vary with group size, but the Pro-

Distribution

TABLE 1 of Alternatives (CLalt) for Experiment* Group size

Power ratio 2:1 5:l

Dyad

Triad

Tetrad

24-12 30-6

24-6-6 30-3-3

24-4-4-4 30-2-2-2

* The first number denotes the alternative of Person S, the “strong” person, and the subsequent number(s) denote the alternative(s) of the weaker member(s) of the group.

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portionality norm predicts that Person S’s proportional share should be invariant over group size. Six prize values were used: 24, 42, 60, 84, 144, and 288 points. The prize of 24 was included as a test of the subjects’ understanding of the situation, and will not be considered in any of the analyses. The two levels of power ratio and the six prize values were crossed. resulting in I2 stimuli. The I2 stimuli were presented to all groups but with a counterbalanced order: Half of the groups were presented with the I2 stimuli in a randomized order, and the other half were presented with the reverse sequence of stimuli. Subjects were informed that their task was to maximize their point totals. They were told that they would be awarded prizes worth up to $2.00 at the end of the experiment, with the value of their prizes dependent on the total points they accumulated over all trials. The prizes consisted of school supplies such as ball point and felt tip pens, pencils, etc., which were displayed in the waiting room. They were also informed that one person-randomly assigned-would have an advantage over the other(s) (have better alternatives). Hence, in awarding prizes at the end of the experiment each person’s performance (points accumulated) would be compared with the performance of previous persons who had been in the same position, rather than with the other persons in the group. This incentive scheme was designed to motivate subjects to maximize their share over all trials. Pilot studies suggested that many subjects assigned to the role of Person S were satisfied with a share that was only slightly greater than the other group members. Hence, this procedure was used to increase the level of aspiration of Person S. A single practtce trial was included in the instructions to familiarize the subjects with the procedure. When the instructions were completed, a short written quiz was administered to guarantee that the subjects had a thorough understanding of the situation. The correct answers to the quiz questions were provided and discussed when necessary. The experimenter then left the room and allowed the group to negotiate freely without interruption.

RESULTS

As was previously mentioned, the prize of 24 points was included to check on subjects’ understanding of the situation. Since the alternatives of the bargainers always sum to 36, all groups should take their alternative rather than divide the 24 points. However, this prize was divided approximately 21% of the time. When questioned about this “irrational” behavior after the experiment, subjects usually gave one of two responses: (1) they hadn’t noticed it or (2) they had previously agreed on how to split the prizes, and the few points involved were not important enough to risk the breakdown of this previous agreement. This highlights the importance of precedence in bargaining (the development of contractual norms, as postulated by Thibaut & Faucheux, 1965), and points out a potential problem with a repeated measures design. All further analyses do not include the data for the prize of 24. Since groups did not always reach agreement, the proportions of groups reaching agreement (across the experimental conditions) were first analyzed. For a total of 420 trials, agreement was reached in 405 (96.4%) of the cases. The 15 instances in which agreement was not reached were scattered across the conditions. Using Goodman’s (1972) log-linear method for analyzing frequency data, the analysis of the frequency of reaching agreement indicated that neither the main effects nor interac-

152

KOMORITA

AND KRAVITZ ,----.

5 : ,

=,

*----a-----------. ‘O.& o-----4 L\I,

OYAD r,, 0

loo

TRIAD

200

300

0

TETRAD

100

200

PRIZE

VALUE

300

0

100

200

300

FIG. 1. Observed values of Ps (hatched curves) and predicted values of Equal Excess norm (solid curves). In each panel, the upper and lower solid curves represent predictions for 5: 1 and 2: 1 conditions, respectively.

lions were significant at the .05 level. Thus, there is no reason to believe that the experimental conditions affected the frequency of reaching agreement. For all subsequent analyses, therefore, cell means were inserted for missing data (15 cases where agreement was not reached), and the df for the relevant error terms were correspondingly reduced. To simplify the analysis, the proportional share of the prize for Person S, denoted Ps, was used as the response measure. For example, for a prize of 60, if Person S negotiated a payoff of 45, Ps = .75. Figure 1 shows the mean values of Ps across the three experimental conditions, and the predicted values of the Equal Excess norm (solid lines). For all three levels of group size, the predictions of the Proportionality norm would be represented by two horizontal lines: at .83 for the 5: 1 condition and at .67 for the 2: 1 condition. For both levels of power ratio, the predictions of the Equality norm would also be represented by horizontal lines: at .50 in the dyad, at .33 in the triad, and at .25 in the tetrad. Values of Ps were converted to arcsin and a 3~2x5 (group size by power ratio by prize) analysis of variance was conducted.3 All three of the main effects and the two-way interactions between all three pairs of variables were significant at the .Ol level. Figure 1 shows that Ps decreases with increasing prize value and group size, and is uniformly greater for the 5: 1 than for the 2: 1 power ratio. The main effect of group size, F(2,39) = 38.93, is inconsistent with the predictions of the Proportionality norm; the main effect of power ratio, F( 1,39) = 81.19, is inconsistent with the predictions of the Equality norm; and the main effect of prize, F(4,141) = 32.60, is inconsistent with the predictions of both the Proportionality and Equality norms. 3 The untransformed values of Ps were also analyzed, and although the F values of the two analyses differed slightly, in no case did the probability levels differ.

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With regard to the significant two-way interactions, Fig. 1 shows that the interaction between prize and group size, F&141) = 3.09, can be attributed to the fact that the effect of prize increases with group size (steeper functions with increasing group size). The interaction between prize and power ratio, F(4,141) = 4.29, can be attributed to the fact that the effect of power ratio is large for small prizes but is negligible for large prizes (two functions converge). Both of these interactions are inconsistent with the predictions of the Proportionality and Equality norms. Finally, the interaction between group size and power ratio, F(2,39) = 9.55, can be attributed to the fact that the effect of power ratio is greater for the dyad than for the triad and tetrad conditions. Although this interaction is not predicted by the Equal Excess norm, it may be due to extra pressure for Person S to conform to Equality in the larger groups. Tests of Three Norms

Although the results of the analysis of variance seem to be most consistent with the predictions of the Equal Excess norm, Fig. 1 shows that there are some notable errors of prediction. To provide a more rigorous test of the three norms, the mean of squared discrepancies between predicted and observed values (proportion for Person S) for each norm were compared. A single mean square error was computed for each group, averaged across prize value and power ratio. A t-test for correlated means, computed over groups in all three group size conditions, was used to compare the accuracy of each-pair of norms.4 The mean square error for the Equal Excess, Equality and Proportionality norms were .020, .038, and .095, respectively. The t-tests indicate that the Equal Excess norm is indeed the most accurate: It is superior to the Proportionality norm: t(41) = 7.09, p < .Ol, and to the Equality norm: t(41) = 3.20, p < .Ol. The Equality norm is more accurate than the Proportionality norm: t(41) = 3.92, p < .Ol. Best-fit analysis. The results of this analysis, combined with the results of the previous analysis, cast serious doubt on the validity of both the Proportionality and Equality norms. However, it might be argued that some groups are conforming to the Equality norm, some to the Proportionality norm, and the proportion of groups conforming to these two norms varies as a function of prize value. In particular, the data of Fig. 1 might be explained by the fact that the proportion of groups using the Proportionality norm decreases as prize value increases, while the pro’ A single analysis of variance using all three norms was not conducted because the error #for such a procedure would be highly spurious, e.g., with 42 independent observations (groups), such a procedure would yield 82 @for the residual (error) variance. Moreover, it would be possible to construct and compare any number of hypothetical models so as to increase the error df.

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TABLE 2 Proportion of Groups for Which the Three Norms Provide the Best Fit* Prize values

Norm

Proportionality Equality Equal excess

Mean

42

60

84

144

288

.I7 .23 .60

.18 .23 .59

.I8 .44 .38

.19 .49 .32

.23 .45 .32

.19 .37 .44

* Data are averaged over group size and power ratio, and are based on proportional share of Person S because weaker players invariably agreed to equal shares among themselves.

portion of groups using the Equality norm increases as prize value increases. To test this hypothesis, the proportion of groups for which each norm was most accurate (yielded the best fit) was determined for each of the 3 x 2 x 5 cells. These data show that for both the 2: 1 and 5: 1 conditions, the Equality norm can be clearly rejected for the dyad, while the Proportionality norm can clearly be rejected for the triad and tetrad. Table 2 shows these data for the 5 prize values, pooled over group size and power ratio. It can be seen that the proportion of groups conforming to the Equality norm indeed increases with prize value; however, there is no change in the proportion of groups conforming to the Proportionality norm. Thus, the accuracy of the Equal Excess norm, relative to the other two norms, cannot be explained by the joint change in the salience and use of the Proportionality and Equality norms. Supplementary analysis. By dividing Person S’s outcome by the prize value we are implicitly assuming that the objective and subjective prize values are isomorphic. If subjective value is a negatively accelerated positive function of objective prize, the predicted (and observed) monotonic decreasing values of Ps as a function of prize could be a scaling artifact, with some other model (e.g., Proportionality) being correct. Consequently, the raw points received by Person S were also examined.5 Since the assumption of homogeneity of variance is grossly violated with raw points as the dependent variable (the ratio of largest to smallest cell variance was approximately 1400: 1) no statistical analysis was performed on these data. However, visual inspection of the data shows a very clear bilinear interaction of group size by prize, as would be predicted by Equation 1. The curves of Si as a function of prize value were not concave downward, as they should be if the Proportionality model were correct, and the relationship between objective and subjective prize values were 5 We would like to thank Michael Birnbaum for suggesting this alternative interpretation and analysis.

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as described above. This indicates that the main effect of prize value is real, and not merely a scaling artifact. The bilinear fan of group size by prize also provides additional support for the Equal Excess model. DISCUSSION

AND CONCLUSIONS

These results demonstrate that reward division in bargaining situations is not a simple function of alternatives, at least when alternatives are operationalized as in this study. None of the three norms of reward division received overwhelming support. Although the Equal Excess norm provided the most accurate description of the data, there were some systematic errors of prediction. The major biases in the predictions of the Equal Excess norm were in the effects of group size and prize value. The Equal Excess norm underestimated Person S’s outcome in the dyad but overestimated it in the triad and tetrad. Person S’s outcome was overestimated for small prize values but underestimated for large prize values. The bias toward equality in larger groups (cf. Fig. 1) suggests an important restriction on the generality of these results. In this study the alternatives of the weaker players were always equal, and because of this common bond they may have presented a unified demand for equality against Person S. Hence, as group size increased, Person S may have been under greater conformity pressures to concede toward equality. This would account for the effect of group size on accuracy of predictions. If, on the other hand, the weaker persons had varying alternatives, they might argue among themselves and thus reduce the pressure on Person S to accept equality. Indeed, in a case where there is one “weak” player and several “strong” players, the “stronger” persons might induce the “weak” person to accept Proportionality. This hypothesis implies that the nature of the interaction between group size and the salience of various norms may depend upon the size of the majority favoring one norm over the others. Thus, the distribution of alternatives of the group members is likely to be an important factor in bargaining situations. The results of this study have theoretical implications for a class of coalition situations in which the prize for the coalition of all players is greater than the prize for any subset. The Bargaining theory of coalition formation (Komorita & Chertkoff, 1973) can be extended to make predictions in such situations, and this theory assumes that the shares of the coalition members should be directly proportional to their expectation!: in alternative coalitions. In a typical coalition situation such expectations in alternative coalitions are uncertain, whereas in the present study there was no uncertainty regarding each person’s alternative. Thus, the results of this study only have indirect implications for the Bargaining theory. Nevertheless, if future research using uncertain alternatives should show that the Equal Excess norm yields more accurate predictions than the

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Proportionality norm, the validity of the Bargaining theory must be questioned. To anticipate such an event, Komorita (Note 1) has proposed a general model based on the Equal Excess norm, and has shown that the predictions of his model are quite accurate in a variety of coalition situations. Finally, the results of this study may also have important theoretical implications for equity theory. Adams’ equity formulation (1965) suggests that outcomes (share of reward) should be proportional to inputs (contribution toward achieving reward). For the two-person case, for example, Adams’ equation specifies that (O1/Z1) = (0,/I,), where 01, II, 02, and Zz denote the outcomes and inputs of Persons 1 and 2, respectively. Assuming that the total outcome (01 + 0,) must equal the prize to be divided, it can be shown that the Equal Excess norm predicts that the difference in outcomes should equal the difference in inputs of the two parties, i.e., (0, - 03 = (II - Zz). This formulation is a simple form of Harris’s (1976, Equation 8) linear equity formula, and Harris has shown that this equation has certain mathematical properties that are desirable in any equity formulation. Thus, in situations where the reward allocation is negotiated among the parties, and where there is a close correspondence between inputs (investments, costs) and the alternatives of the parties, the results of this study suggest that Adams’ ratio equity formula may be inappropriate. REFERENCES Adams, J. S. Inequity in social exchange. In L. Berkowitz (Ed.), Advances in experimental social psychology, Vol. 2, New York: Academic Press, 1965. Aumann, R. J., & Maschler, M. The bargaining set for cooperative games. In M. Dresher, L. S. Shapley, & A. W. Tucker (Eds.), Advances in game theory. Annals of Mathematics Study 52. Princeton: Princeton University Press, 1964. French, J. R. P., & Raven, B. The bases of power. In D. Cartwright (Ed.), Studies in social power. Ann Arbor: University of Michigan Press, 1959. Gamson, W. A. Experimental studies of coalition formation. In L. Berkowitz (Ed.), Advances in experimental social psychology, Vol. 1. New York: Academic Press, 1964. Goodman, L. A. A modified multiple regression approach to the analysis of dichotomous variables. American Sociological Review, 1972, 37, 28-46. Harris, R. J. Handling negative inputs: On the plausible equity formula. Journal ofExperimental Social Psychology, 1976, 12, 194-209. Kelley, H. H., & Arrowood, A. J. Coalitions in the triad: Critique and experiment. Sociometry, 1960, 23, 231-244. Komorita, S. S. Negotiating from strength and the concept of bargaining strength. Journal for the Theory of Social Behaviour, 1977, 7, 65-79. Komorita, S. S., & Barnes, M. Effects of pressures to reach agreement in bargaining. Journal of Personality & Social Psychology, 1969, 13, 245-252. Komorita, S. S., & Chertkoff, J. M. A bargaining theory of coalition formation. Psychological Re\*iew, 1973, 80, 149-162. Lawler, E. J., & Bacharach, S. B. Outcome alternatives and value as criteria for multistrategy evaluations. Journal of Personality & Social Psychology, 1976, 34, 885-894. Nash, J. F. The bargaining problem. Econometrica, 1950, 18, 155-162.

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Nash, J. F. Two-person cooperative games. Econometrica, 1953, 21, 128-140. Pruitt, D. G., & Drews, J. L. The effect of time pressure, time elapsed, and opponents’ concession rate on behavior in negotiation. Journal of Experimental Social Psychology, 1969, 5, 43-60. Rubin, J. Z., & DiMatteo, M. R. Factors affecting the magnitude of subjective utility parameters in a tacit bargaining game. Journal of Experimental Social Psychology, 1972, 8, 412-426. Shapley, L. S. A value for n-person games. In H. W. Kuhn & A. W. Tucker (Eds.), Contributions to the theory of games, II. Princeton: Princeton University Press, 1953. Thibaut, J., & Faucheux, C. The development of contractual norms in a bargaining situation under two types of stress. JournalofExperimentalSocial Psychology, 1965,1,89-102. Thibaut, J., & Kelley, H. H. The social psychology of groups. New York: Wiley, 1959. Walster, R., Berscheid, E., & Walster, G. W. New directions in equity research. Journal of Personality & Socicl Psychology, 1973, 25, 151-176. Yukl, G. A. Effects of information, payoff magnitude, and favorability of alternative settlement on bargaining outcomes. Journal of Social Psychology, 1976, 98, 269-282.

REFERENCE

NOTE

1. Komorita, S. S. An equal excess model of coalition University of Illinois.

formation.

Unpublished manuscript,