Motivational determinants of coalition formation

Coalition preferences of 300 male and female subjects were ascertained under varying motivational conditions. Two of the experimental conditions repeated the typical three-person coalition paradigm, with a monetary reward (extrinsic motivation) offered for the winning of a luck-determined game. In a third condition, skill rather than luck influenced the outcome and no monetary reward was given for winning (intrinsic motivation). Two additional conditions examined coalition preferences in a mixed-motive situation, with either a small or a large monetary reward offered for winning a skill-related game. In the extrinsic motivation condition, the low and the medium resource persons typically desired to coalesce, contrary to the wishes of the excluded, high resource player. In contrast, the coalition between the low and the medium resource persons also was preferred by the high resource player in the intrinsic motivation condition. Coalition conflict was intermediate in the mixed-motive conditions. In sum, it was demonstrated that coalition formation and interpersonal conflict are dependent upon the motivational determinants of group activity.     

Variability in payoff disbursement in coalition formation experiments

Results from 680 plays, gathered in four different 3-person characteristic function game experiments, are summarized to show that there is considerable inter-group variability in payoff disbursement in coalition formation experiments that does not decrease with practice. This Variability is inconsistent with models predicting unique payoff vectors, one for each coalition structure. Data from a 3-person game experiment by Komorita and Kravitz are then employed to test and corroborate a recently proposed model, which predicts a range of payoff vectors in which each point depends on a single parameter interpretable as a standard of fairness.     

The interplay of self‐interest and equity in coalition formation

In this paper we investigated the interplay of self‐interest and equity concerns in coalition formation by manipulating the number of units in which the coalition payoff is made available, and by manipulating the way people are allowed to interact. Results of three experiments showed that when the coalition payoff was such that members of each possible coalition could obtain an equitable payoff share, the outcome tended to be coalitions that also maximized the payoff of its members. However, when the payoff was such that people had to make trade‐offs between maximizing their payoff share and obtaining an equitable payoff share, it took longer to form a coalition and it was harder to maintain a coalition. Moreover, depending on the way people were allowed to interact, the final outcome was a coalition that maximized the payoff of its members or a coalition that provided them with an equitable payoff share. Copyright © 2004 John Wiley & Sons, Ltd.     

The role of sex and personality in the prenegotiation stage of coalition formation

Research in the area of sex differences in coalitional behavior has produced inconsistent results that may be partially resolved through an examination of personality and attitudinal differences between males and females. The responses of males and females to the Shure and Meeker Personality/Attitude Schedule were analyzed and the sexes differed in their elevation on six major factors. A subsample of each sex participated in a coalition game situation. Four of the six personality and attitude factors were related to prenegotiation stage indices of coalition formation. It was suggested that the role of sex differences in coalitional behavior may be mediated by sex role socialization differences.     

Computer controlled research on bargaining and coalition formation

Described in this paper is a research paradigm, written as a set of computer programs, to conduct on-line bargaining and coalition formation experiments within the characteristic function game framework. The structure of the paradigm is outlined, an example is presented and discussed, and further extensions of the program are briefly discussed.     

Strength-is-Weakness: The (ir)relevant relation between resources and payoffs in coalition formation

A key observation in coalition formation is that bargainers who control many resources are often excluded from coalitions by bargainers who control few resources, the Strength-is-Weakness effect. We argue that this effect is contingent on whether resources provide a legitimate claim to be included in a coalition. Across three incentivized coalition experiments (n = 2745; 915 triads), three participants (player A had four resources, player B had three resources, player C had two resources) negotiated about a payoff of 90 monetary units. Depending on condition, these resources were obtained randomly, earned, or earned and proportionally linked to the payoff. Results showed player As were less included when resources were obtained randomly and more often included in coalitions when resources were earned and/or proportionally linked to the payoff. This provides evidence that the Strength-is-Weakness is contingent on the legitimacy of the resources.     

The equal division kernel: An equity approach to coalition formation and payoff distribution in N-person games

Most existing models of coalition formation and payoff distribution in groups rest upon normative considerations and are ambiguous in their predictions insofar as they do not determine which of several coalitions will most probably result. The paper sketches the basic features of a model derived from social psychological exchange-and equity-theory which predicts coalitions and payoff distributions for a variety of situations. The evaluation of the model by the results of several experiments indicates that it provides a reasonable starting point for further theoretical developments that are based empirical studies.     

Do-no-harm in coalition formation: Why losses inhibit exclusion and promote fairness cognitions

Previous research on coalition formation has established that people will not hesitate to exclude others in order to maximize their payoff. The authors propose that this view is too narrow and that the decision to exclude depends on the valence of the payoff. Consistent with a “do-no-harm” hypothesis, Experiment 1 showed that participants were more reluctant to exclude in order to minimize their losses than to maximize their gains. Experiment 2 replicated this effect and showed that participants were most affected by payoff valence when they were disposed to consider the viewpoint of others. Additional analyses revealed that participants were more motivated by fairness (Experiment 1) and that fairness was more cognitively accessible (Experiment 2) when payoffs were negative rather than positive.     

The principle of excluded middle in quantum logic

The principle of excluded middle is the logical interpretation of the law V A v in an orthocomplemented lattice and, hence, in the lattice of the subspaces of a Hilbert space which correspond to quantum mechanical propositions. We use the dialogic approach to logic in order to show that, in addition to the already established laws of effective quantum logic, the principle of excluded middle can also be founded. The dialogic approach is based on the very conditions under which propositions can be confirmed by measurements. From the fact that the principle of excluded middle can be confirmed for elementary propositions which are proved by quantum mechanical measurements, we conclude that this principle is inherited by all finite compound propositions. For this proof it is essential that, in the dialog-game about a connective, a finite confirmation strategy for the mutual commensurability of the subpropositions is used.     

Resources and alternatives in coalition formation: The effects on payoff,self‐serving behaviour,and bargaining length

A consistent finding in coalition research is that the payoff of coalition members is related to (a) the resources they contribute to the coalition, and to (b) the number of alternative coalitions they can form. These two factors are, however, often intertwined. A greater number of resources tends to go hand in hand with a greater number of alternatives, leaving unanswered how both factors affect coalition behaviour. This paper attempts to clarify the interplay of resources and alternatives by disentangling the two in a newly developed coalition paradigm. Results indicated that participants base their payoff allocation on both resources and alternatives, but suggest that self‐serving behaviour is more related to alternatives. Furthermore, resources and alternatives had a distinct effect on the bargaining process. It was shown that differences in alternatives led to longer bargaining. Copyright © 2004 John Wiley & Sons, Ltd.     

The faultline activation process and the effects of activated faultlines on coalition formation,conflict, and group outcomes

This research examines the effects of group faultline activation on coalition formation, conflict, and group outcomes. We distinguish between dormant faultlines (potential faultlines based on demographic characteristics) and activated group faultlines (members actually perceive subgroups based on the demographic characteristics) and hypothesize that while dormant faultlines do not automatically turn into active group divisions, a group’s entitlement configuration can activate divisions among group members. Study 1 was a construct validity study to verify the psychometric properties of the activated group faultline measure and explain its connection to other process variables. In Studies 2 and 3, we tested our hypotheses and found that groups with activated faultlines were more likely to form coalitions, have high levels of group conflict, and lower levels of satisfaction and group performance than dormant faultline groups. Furthermore, team identification moderated the effects of activated faultlines on group processes such that a strong workgroup identity decreased the likelihood that activated faultlines led to coalition formation and conflict.     

Quantified coalition logic

We add a limited but useful form of quantification to Coalition Logic, a popular formalism for reasoning about cooperation in game-like multi-agent systems. The basic constructs of Quantified Coalition Logic (QCL) allow us to express such properties as “every coalition satisfying property P can achieve φ” and “there exists a coalition C satisfying property P such that C can achieve φ”. We give an axiomatisation of QCL, and show that while it is no more expressive than Coalition Logic, it is nevertheless exponentially more succinct. The complexity of QCL model checking for symbolic and explicit state representations is shown to be no worse than that of Coalition Logic, and satisfiability for QCL is shown to be no worse than satisfiability for Coalition Logic. We illustrate the formalism by showing how to succinctly specify such social choice mechanisms as majority voting, which in Coalition Logic require specifications that are exponentially long in the number of agents.     

Bargaining ability,the utility of playing a game,and models of coalition formation

A utility function for playing a given position in a game is developed as a natural extension of the utility function which defines the rewards available in the game. This function is determined by a player's opinion of his bargaining ability. A characterization of such utilities is obtained which generalizes previous results that the Shapley value and Banzhaf-Coleman index are both cardinal utility functions which reflect different bargaining abilities. The approach taken here is related to models of coalition formation.     

Effects of alternatives in coalition bargaining

A critical factor in bargaining and coalition formation is the alternative outcomes of the bargainers if an agreement cannot be reached. In some situations bargainers have individual alternatives while in other situations their alternatives must be negotiated with others. The purpose of this study was to contrast the effects of one-person and two-person alternatives on coalition outcomes. The second purpose of the study was to contrast the predictions of four theories of coalition formation: bargaining theory, equal excess model, Shapley value, and a special case of equity theory. The results indicate that one-person alternatives enhance the bargaining strength of the stronger players more than two-person alternatives. The predictions of the equal excess model and the Shapley value were more accurate than the predictions of bargaining theory and equity theory. However, the greater accuracy of the equal excess model and the Shapley value may be restricted to situations in which the bargainers have one-person rather than two-person alternatives.     

Self-interest and fairness in coalition formation: A social utility approach to understanding partner selection and payoff allocations in groups

In this chapter we present a social utility approach to coalition formation. The central tenet of our approach is that outcome allocations and partner selection in multiparty situations are affected by self-interest and fairness. Inspired by the social utility model we argue that the relative weight assigned to both components is affected by structural aspects of the situation and individual characteristics of the negotiators. We first investigate how coalition bargainers substantiate their coalition demands. We show that bargainers are self-serving in their choice of allocation rules, indicating that perceptions of fairness can be coloured by self-interest. Second, we investigate how the alignment of self-interest and fairness fosters the formation of coalitions that maximise the payoffs of its members. Finally, we present a series of experiments that expands the notion of being fair to those who are excluded from a coalition. We show that bargainers are reluctant to benefit themselves when this harms the outcomes of others and that this is dependent on personal factors (e.g., social value orientations), situational factors (e.g., the valence of outcomes), and whether bargainers negotiate in an interindividual or in an intergroup setting.     

Normalization and excluded middle. I

The usual rule used to obtain natural deduction formulations of classical logic from intuitionistic logic, namely is stronger then necessary, and will give classical logic when added to minimal logic. A rule which is precisely strong enough to give classical logic from intuitionistic logic, and which is thus exactly equivalent to the law of the excluded middle, is It is a special case of a version of Peirce's law: In this paper it is shown how to normalize logics defined using these last two rules. Part I deals with propositional logics and first order predicate logics. Part II will deal with first order arithmetic and second order logics. This research was supported in part by grants EQ1648, EQ2908, and CE 110 of the program Fonds pour la Formation de Chercheurs et l'aide à la Recherche (F.C.A.R.) of the Quèbec Ministry of Education.