THE INCOMPLETE‐INFORMATION SPLIT‐STREAM FISH WAR: EXAMINING THE IMPLICATIONS OF COMPETING RISKS

ABSTRACT. . It is now widely recognized that climactic regime shifts, which aperiodically alter a harvested fish stock's biomass and spatial distribution, may lead to distorted fisheries management decisions which negatively impact the fishery, both biologically and economically. This is particularly true for trans‐boundary migratory stocks, where optimal management relies on coordination among independent nation‐states. Unanticipated changes in stock distribution and abundance can upset expectations of national authorities, leading them to sanction inappropriate harvesting levels by their separately managed fleets targeting the same breeding fish stock. Our theoretical studies are based on a spatially‐distributed stochastic model, which we have called the “split‐stream model,‘ where two separately managed fleets harvest simultaneously at two separate sites. Our key assumption is that competing fleet managers, when harvesting noncooperatively, hold incomplete and asymmetric private information of current stock recruitment and spatial distribution. When subsequently negotiating to coordinate their harvests, they agree that they will share their information and then bargain over partition of the gains from their cooperation. This bargaining process takes into account the fleet's relative competitive strengths, particularly due to private information asymmetries. In this present article we introduce a more complex information structure than had been assumed in our earlier work (McKelvey and Golubtsov [2002], McKelvey, Miller and Golubtsov [2003], Mckelvey et al. [2004]). Specifically, both stock‐growth and stock‐split parameters vary stochastically and asynchronously. Thus, when harvesting noncooperatively, each fleet may possess private knowledge which is unavailable to the other. We examine the interplay of the harvesting game's information structure with other fishery characteristics, such as the fleets' economics and operating characteristics and their attitudes toward risk, to determine the implications of such structure for the outcome of the harvesting game. All of these changes are made to capture new conceptual phenomena and expand the range of applicability of the model.     

Power,Embedded Games,and Coalition Formation

Applications of game theory frequently presume but do not show that social structures contain games. This study shows that multiple games are embedded in strong power structures and that power is exercised because 1) the game of those low in power contains a dilemma whereas 2) the game of those high in power does not. As in previous analyses, we find those low in power play the Prisoner's Dilemma game. New to this analysis is the discovery that those high in power play the Privileged game, a game with no dilemma. Also new is the extension of the analysis to the design of coalitions. That extension shows that, when coalition formation succeeds, it eliminates the dilemma of those low in power by transforming their game from Prisoner's Dilemma to Privileged. By contrast, exactly the same coalition structure does not alter the game played by those high in power. Applying well-known game theoretic solution concepts, we predict that low power coalitions will countervail power, but that coalitions of those high in power will not affect power exercise. Experiments testing this theory investigate 1) coalitions of those high in power, 2) low power coalitions organized against multiple high power positions, and 3) opposed coalitions struggling for power against each other. Results strongly support the theory.     

Coalitional unanimity versus strategy-proofness in coalition formation problems

This paper examines coalition formation problems from the viewpoint of mechanism design. We consider the case where (i) the list of feasible coalitions (those coalitions which are permitted to form) is given in advance; and (ii) each individual’s preference is a ranking over those feasible coalitions which include this individual. We are interested in requiring the mechanism to guarantee each coalition the “right” of forming that coalition at least when every member of the coalition ranks the coalition at the top. We name this property coalitional unanimity. We examine the compatibility between coalitional unanimity and incentive requirements, and prove that if the mechanism is strategy-proof and respects coalitional unanimity, then for each preference profile, there exists at most one strictly core stable partition, and the mechanism chooses such a partition whenever available. Further, the mechanism is coalition strategy-proof and respects coalitional unanimity if, and only if, the strictly core stable partition uniquely exists for every preference profile.     

How do coalitions get built? Evidence from an extensive form coalition game with and without communication

In the laboratory, we investigate a non-cooperative three-person coalition game with externalities and the opportunity to extend existing coalitions. One bargainer, the builder, can propose and build a coalition over two stages. We examine the hypothesis that both absolute and relative payoffs affect the coalition formation process (and outcome). We observe many inefficient two-person final coalitions, and that the distribution of outcomes is sensitive to the constellation of both absolute and relative payoffs. Relative payoffs appear to be applied more myopically than has been observed in bilateral sequential bargaining games or suggested by social preference models. We hypothesize that the prevalence of two-person coalitions stems from builder’s uncertainty about individual acceptance thresholds. In fact, allowing nonbinding communication among the bargainers increases the prevalence of efficient coalitions. The main implication is that efficient coalition building involves strategies for mitigating the strategic uncertainty inherent in building coalitions.     

Self-enforcing coalitions with power accumulation

Agents endowed with power compete for a divisible resource by forming coalitions with other agents. The coalition with the greatest power wins the resource and divides it among its members. The agents’ power increases according to their share of the resource.We study two models of coalition formation where winning agents accumulate power and losing agents may participate in further coalition formation processes. An axiomatic approach is provided by focusing on variations of two main axioms: self-enforcement, which requires that no further deviation happens after a coalition has formed, and rationality, which requires that agents pick the coalition that gives them their highest payoff. For these alternative models, we determine the existence of stable coalitions that are self-enforcing and rational for two traditional sharing rules. The models presented in this paper illustrate how power accumulation, the sharing rule, and whether losing agents participate in future coalition formation processes, shape the way coalitions will be stable throughout time.     

MODELING AND MEASURING PRODUCTION PROCESSES FOR A MULTI‐SPECIES FISHERY: ALTERNATIVE TECHNICAL EFFICIENCY ESTIMATES FOR THE NORTHERN SPAIN HAKE FISHERY

ABSTRACT. The economic performance of fisheries is difficult to measure, due to the importance of (multi‐species) biological dynamics, property rights and regulatory issues affecting fishermen's behavior and efficiency. However, an understanding of performance patterns is essential for enhancing the economic and biological viability of fisheries. In this paper we estimate and evaluate alternative primal stochastic approaches to modeling and measuring technical efficiency for the Northern Spain hake fishery. We then compare the resulting efficiency measures to identify variations in their potential interpretation, and application to policy guidance. We find that multi‐output models are more theoretically and empirically justifiable than aggregate output production function models, and provide additional policy‐relevant insights, but that relative production and efficiency estimates are not sub‐stantively affected by model specification.     

分销供应链中竞争零售商联盟的稳定性

针对由单一供应商和三个相互竞争零售商组成的两层分销供应链系统,在三种不同的博弈框架下,采用合作博弈论中短视的Nash稳定性概念与远视的最大一致集(LCS)概念研究了供应商与不同零售商联盟间的定价博弈,分别讨论了不同类型零售商联盟的稳定性。发现不论是在供应商处于领导地位,还是在零售商处于领导地位的市场中,当竞争强度较弱时,大联盟不是短视零售商联盟的稳定结构,却有可能是远视零售商联盟的稳定结构;当竞争强度较强时,则无论是短视零售商还是远视零售商都以大联盟为稳定结构,但是,在供应商处于领导地位的市场中,远视零售商形成大联盟的阈值较高;在供应商和零售商地位相同的市场中,大联盟则是远视零售商和短视零售商共同的稳定结构。     

Common pool resources with support

We examine the role of support for coalition stability in common pool resource games such as fisheries games. Some players may not want to join a coalition that jointly manages a resource. Still, because they benefit from spillovers, they may want to support the coalition with a transfer payment to set incentives for others to join. We find that the impact of support on equilibria of this game is limited to games with three or five players. Recommendations for Resource Managers

• Coalitions may be able to effectively manage common pool resources such as fisheries but such coalitions are often not stable due to free-rider incentives.
• We explore the impact of a transfer scheme that can improve this coalition stability which would lead to larger and more effective coalitions.
• Our results show that this new transfer scheme works only for cases where the number of players is small.

     

Economic and biological risk analysis of the Norwegian spring‐spawning herring fishery

The purpose of this paper is to study the biological and economic risks involved in the management of the Norwegian springspawning herring fishery. We use a discrete time and agestructured model based on historical data. The current paper investigates, under different levels of fishing mortalities, the risk probabilities related to the time behaviour of the spawning stock and profit. We show that the exploitation of the herring stock is vulnerable to small changes in harvesting and price level.     

The Myerson value for complete coalition structures

In order to describe partial cooperation structures, this paper introduces complete coalition structures as sets of feasible coalitions. A complete coalition structure has a property that, for any coalition, if each pair of players in the coalition belongs to some feasible coalition contained in the coalition then the coalition itself is also feasible. The union stable structures, which constitute the domain of the Myerson value, are a special class of the complete coalition structures. As an allocation rule on complete coalition structures, this paper proposes an extension of the Myerson value for complete coalition structures and provides an axiomatization.     

Coalition behaviour in n‐person conflicts†

This paper presents a theory of behaviour in n‐person conflicts. The theory and its solution are predicated on the inter‐dependency of coalition formation and pay‐off determination in an n‐person conflict. The solution, therefore, involves not only pay‐off determination but also coalition formation in the game. The theory is developed using mathematical notions of fixed points together with some behavioural theories about choice behaviour and interdependency of persons in competitive situations. It predicts not only the final state of coalition formation but also transient choices and coalitions in the games. Finally, the model is tested on some experimental games of W. Riker.     

On connected coalitions in dominated simple games

In a book by Axelrod it is claimed that, in the presence of well defined policy order, only connected coalitions form. Here we investigate the compatability of Axelrod's hypothesis with several hypotheses (about coalition formation in dominated simple game) that were formulated by Peleg.     

Stability likelihood of coalitions in a two-stage cartel game: An estimation method

Existing formulations of a cartel game aim at finding stable coalitions, i.e. a coalition is labelled stable or not stable. Uncertainty about the underlying structure and/or parameter values gives rise to sensitivity or uncertainty analysis. In this paper we follow a probabilistic robustness concept: What is the probability a product, design or policy really fulfils the requirements or properties it is expected to. Following this idea, we introduce the concept of stability likelihood: What is the probability a coalition can be labelled as stable. Methods are described based on Monte Carlo Simulation and Directional Simulation to estimate such a probability and we illustrate the performance for several cases.     

COALITIONS IN INTERNATIONAL FISHERIES MANAGEMENT

Abstract We show that with symmetric agents, noncooperation is the only stable coalition structure in a fishery with more than two countries. In the case of asymmetric fishing nations, partial or full cooperation may be stable even if the number of countries exceeds two. These are important results for recent fisheries economics papers that have not allowed for coalition formation. As an example how of one can use the model, we study the problem of new entrants into Regional Fisheries Management Organizations (RFMOs). We show that depending on the economic structure of the fishery, new entrants may make cooperation more difficult or easier.     

Contractually stable networks

We consider situations where players are part of a network and belong to coalitions in a given coalition structure. We propose the concept of contractual stability to predict the networks that are going to emerge at equilibrium when the consent of coalition partners is needed for adding or deleting links. Two different decision rules for consent are analyzed: simple majority and unanimity. We characterize the coalition structures that make the strongly efficient network contractually stable under the unanimity decision rule and the coalition structures that sustain some critical network as contractually stable under the simple majority decision rule and under any decision rule requiring the consent of any proportion of coalition partners. Requiring the consent of coalition members may help to reconcile stability and efficiency in some classical models of network formation.     

Coalitional games and contracts based on individual deviations

We study what coalitions form and how the members of each coalition split the coalition value in coalitional games in which only individual deviations are allowed. In this context we employ three stability notions: individual, contractual, and compensational stability. These notions differ in terms of the underlying contractual assumptions. We characterize the coalitional games in which individually stable outcomes exist by means of the top-partition property. Furthermore, we show that any coalition structure of maximum social worth is both contractually and compensationally stable.     

Aggregate Wind Power Production via Coalitional Games and Optimal Control

In this paper, benefits from aggregating independent wind power producers are analyzed in a scenario, in which the producers willingly form coalitions to increase their expected profits. For every deviation from the declared contract, the coalition is penalized and a cost is paid, if the producers want to update their contract. The underlying idea is that coalitions reduce the risk of being penalized. The main contribution of this paper is a new market model and an allocation mechanism based on optimal control and coalitional games with transferable utilities. Optimal control is used to obtain the optimal contract size, while coalitional games provide an insight on stable revenue allocations, namely allocations, that make the grand coalition preferable to all producers.     

Government formation in a two dimensional policy space

Given any allocation of parliament seats among parties, we characterize all the stable government configurations (supported by at least a majority of the parliament) in terms of winning coalitions and policy outcomes. We consider a two dimensional policy space and we assume that there are four parties that care mainly about holding office, and only instrumentally about policy. We find that for any distribution of seats in the parliament only two scenarios are possible: either there is a party that is a member of almost all equilibrium coalitions (dominant party scenario) or there is a party that is never a member of an equilibrium coalition (dominated party scenario). We characterize the key party for each possible scenario and we show that it is sufficient that the key party has intense preferences over one the issues to guarantee the formation of a stable government coalition.     

微分对策中的联盟解

提出时间区间[t_0,∞)上的n人微分对策两阶段联盟解. 在第一阶段不能形成大联盟的假设是自然的,即源于这一思想. 在第一阶段以联盟作为局中人的对策中计算得到其纳什均衡,之后对每个联盟的收益按Shapley值进行分配. 一个n人微分减排模型的例子阐明了上述结果.     

Coalitions and payoffs in three‐person sequential games: Initial tests of two formal models

In this paper we develop two formal models predicting coalitions and payoffs among rank striving players in a sequential three‐person game. We test the models’ predictions with data from a laboratory study of eleven male triads. Each triad plays a sequence of games; in each game a two‐person coalition forms and divides the coalition's point value between the two coalition partners. Participants know that the sequence of games will end without warning at a randomly chosen time; at the sequence's end each player's monetary payoff is a linear function of the rank of his accumulated point score, relative to those of the other members of his triad. The complexity of this situation prevents players and analysts from representing it as a single game; thus they are unable to use n‐person game theory to identify optimal strategies. Consequently, we assume that players, unable to develop strategies that are demonstrably optimal in the long run, adopt certain bargaining heuristics and surrogate short run objectives.

The two models follow the same basic outline; they differ, however, in the planning horizon they assume players to use. Proceeding from a priori assumptions concerning each player's decision calculus and the bargaining process, the two models state the probability that each coalition forms and predict the point divisions in the winning coalition. The laboratory data provide consistently strong support for the predictions of both models.