Thèses : « Formation de coalition »

1

Winschel, Evguenia. « Essays on coalition formation ». [S.l. : s.n.], 2007. http://nbn-resolving.de/urn:nbn:de:bsz:180-madoc-20457.

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Hojnacki, Marie Elizabeth. « Coalition formation among organized interests / ». The Ohio State University, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487856906261803.

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Barton, Levi L. « Agent-Organized Network Coalition Formation ». DigitalCommons@USU, 2008. https://digitalcommons.usu.edu/etd/206.

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This thesis presents work based on modeling multi-agent coalition formation in an agent organized network. Agents choose which agents to connect with in the network. Tasks are periodically introduced into the network. Each task is defined by a set of skills that agents must fill. Agents form a coalition to complete a task by either joining an existing coalition a network neighbor belongs to, or by proposing a new coalition for a task no agents have proposed a coalition for. We introduce task patience and strategic task selection and show that they improve the number of successful coalitions agents form. We also introduce new methods of choosing agents to connect to in the network and compare the performance of these and existing methods.

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Bäck, Hanna. « Explaining coalitions evidence and lessons from studying coalition formation in Swedish local government / ». Uppsala : Uppsala Universitet, 2003. http://catalog.hathitrust.org/api/volumes/oclc/53332399.html.

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DeJong, Paul. « COALITION FORMATION IN MULTI-AGENT UAV SYSTEMS ». Master's thesis, University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2712.

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Coalitions are collections of agents that join together to solve a common problem that either cannot be solved individually or can be solved more efficiently as a group. Each individual agent has capabilities that can benefit the group when working together as a coalition. Typically, individual capabilities are joined together in an additive way when forming a coalition. This work will introduce a new operator that is used when combining capabilities, and suggest that the behavior of the operator is contextual, depending on the nature of the capability itself. This work considers six different capabilities of Unmanned Air Vehicles (UAV) and determines the nature of the new operator in the context of each capability as coalitions (squadrons) of UAVs are formed. Coalitions are formed using three different search algorithms, both with and without heuristics: Depth-First, Depth-First Iterative Deepening, and Genetic Algorithm (GA). The effectiveness of each algorithm is evaluated. Multi agent-based UAV simulation software was developed and used to test the ideas presented. In addition to coalition formation, the software aims to address additional multi-agent issues such as agent identity, mutability, and communication as applied to UAV systems, in a realistic simulated environment. Social potential fields provide a means of modeling a clustering attractive force at the same time as a collision-avoiding repulsive force, and are used by the simulation to maintain aircraft position relative to other UAVs.
M.S.Cp.E.
Department of Electrical and Computer Engineering
Engineering and Computer Science
Computer Engineering

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Khan, Majid Ali. « Coalition formation and teamwork in embodied agents ». Doctoral diss., University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2711.

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Embodied agents are agents acting in the physical world, such as persons, robots, unmanned air or ground vehicles and so on. These types of agents are subject to spatio-temporal constraints, which do not exist for agents acting in a virtual environment. The movement of embodied agents is limited by obstacles and maximum velocity, while their communication is limited by the transmission range of their wireless devices. This dissertation presents contributions to the techniques of coalition formation and teamwork coordination for embodied agents. We considered embodied agents in three different settings, each of them representative of a class of practical applications. First, we study coalition formation in the one dimensional world of vehicles driving on a highway. We assume that vehicles can communicate over short distances and carry agents which can advise the driver on convoy formation decisions. We introduce techniques which allow vehicles to influence the speed of the convoys, and show that this yields convoys which have a higher utility for the participating vehicles. Second, we address the problem of coalition formation in the two dimensional world. The application we consider is a disaster response scenario. The agents are forming coalitions through a multi-issue negotiation with spatio-temporal components where the coalitions maintain a set of commitments towards participating agents. Finally, we discuss a scenario where embodied agents form coalitions to optimally address dynamic, non-deterministic, spatio-temporal tasks. The application we consider is firefighters acting in a disaster struck city.
Ph.D.
School of Electrical Engineering and Computer Science
Engineering and Computer Science
Computer Engineering PhD

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Pycia, Marek. « Essays on economic design and coalition formation ». Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/34513.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Economics, 2006.
Includes bibliographical references.
This thesis consists of three essays on economic design and coalition formation. The first chapter studies the stability of many-to-one matching, such as matching between students and colleges or interns and hospitals. Complementarities and peer effects are inherent in many such matching situations. The chapter provides the first sufficient condition for stability that may be used to study matching with complementarities and peer effects. The condition offered is shown to be also necessary for stability in some matching problems. The second chapter provides a sufficient condition for the non-emptiness of the core in coalition formation such as the formation of clubs, partnerships, firms, business alliances, and jurisdictions voting on public goods. The condition is formulated for settings in which agents first form coalitions and then each coalition realizes a payoff profile from the set of available alternatives via a mechanism. In particular, there exists a core coalition structure if the payoffs are determined in the Tullock rent-seeking game or Nash bargaining. The core might be empty if the payoffs are determined by the Kalai-Smorodinsky or Shapley bargaining solutions.
(cont.) The chapter also determines the class of linear sharing rules and regular Pareto-optimal mechanisms for which there are core coalition structures. The third chapter studies the multidimensional screening problem of a profit-maximizing monopolistic seller of goods with multiple indivisible attributes. The buyer's utility is buyer's private information and is linear in the probabilities of obtaining the attributes. The chapter solves the seller's problem for an arbitrary number of attributes when there are two types of buyers, adding a new simple example to the few known examples of solved multidimensional screening problems. When there is a continuum of buyer types, the chapter shows that generically the seller wants to sell goods with some of the attributes partly damaged, stochastic, or leased on restrictive terms. The often-studied simple bundling strategies are shown to be generically suboptimal.
by Marek Pycia.
Ph.D.

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Karos, Dominik [Verfasser]. « Power, Control, and Coalition Formation / Dominik Karos ». Aachen : Shaker, 2013. http://d-nb.info/1050344871/34.

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Dang, Viet Dung. « Coalition formation and operation in virtual organisations ». Thesis, University of Southampton, 2004. https://eprints.soton.ac.uk/260239/.

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The concept of Virtual Organisations (VOs) or Virtual Enterprises (VEs) is rapidly emerging as an important topic in many areas of computing including e-commerce, grid computing and the semantic Web. One reason for this interest is that VOs provide a means of bringing together a number of autonomous stakeholders in a dynamic fashion in order to address a specific problem or niche. These agents then work together for some period of time and then disband when it is deemed appropriate to do so. There are, however, many technical, social and economic issues associated with this VO lifecycle (i.e. creation, operation, maintenance and dissolution) that need to be addressed before VOs can be considered to be practicable. While previous technical work on VOs has concentrated on providing tools to support different aspects of the VO lifecycle, comparatively little work has focused on the mechanisms for automated VO creation, operation and maintenance. To address this shortcoming, this research aims to study and design mechanisms for the VO creation, operation and maintenance phases. In this thesis, our approach is to use combinatorial auctions and coalition formation mechanisms. In particular, novel algorithms for clearing multi-unit single-item and multi-unit combinatorial auctions have been developed as a means of tackling VO creation and one part of VO maintenance. A novel algorithm for coalition structure generation has also been developed to address VO operation and another part of VO maintenance.

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Lee, Daesik. « Essays on coalition formation under asymmetric information ». Diss., Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/53567.

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We consider the applicability of the Revelation Principle under the possibility of collusive behavior among players in some Bayesian framework. In doing this, since the coalition formation itself suffers information asymmetry problems, we assume that the coalition is formed if the colluding parties can successfully find some coalitional mechanism whose outcome is a set of messages in the original mechanism. Recently Cremer [1986] proposes a coalitional mechanism in the framework of the well known Vickrey-Clark-Groves mechanism. We assume that the agents successfully collude if they can find coalitional a mechanism such that (i) coalitional mechanism is incentive-compatible and (ii) the payoff of this mechanism is strictly Pareto-improving in terms of the agent’s expected utility. Our analysis is undertaken in a one principal/two agent framework. We first ünd that the Revelation Principle is still applicable in the pure adverse selection model. We then extend this result to a model with both adverse selection and moral hazard aspects. Finally, we consider a three-tier principal/supervisor/agent hierarchical organization, as in Tirole (1986). We explicitly present the coalitional mechanism as a side-contract between the supervisor and the agent. We apply the previous result of applicability of the Revelation Principle and characterize the coalition-proof mechanism. We find that the principal can design an optimal collusion free contract with some additional cost by specifying proper individual and coalitional incentive-compatibility conditions and individual rationality conditions. Moreover, we find that the results of Tirole (1986)’s paper hinge on the fact that he considers only “hard,” verifiable, information.
Ph. D.

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Lindgren, Stina. « Coalition formation during turbulence : A large-n study examining the effects of economic and political instability on government-coalition formation ». Thesis, Uppsala universitet, Statsvetenskapliga institutionen, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-430607.

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This thesis examines the effects of economic and political turbulence on coalition-formation across 37 EU and OECD democracies. Utilizing the existing potential-coalitions research, it analyzes how increases in turbulence affect common variables predicted to determine which coalitions are chosen of all potential cabinets following an election. These variables drawn from the coalition-formation field are examined using a conditional logit regression model with interaction effects, and results indicate that both political and economic turbulence highly affect the way coalition formation is carried out, although the effects of the two turbulence types vary. During economic turbulence larger coalitions appear to be warranted, although results simultaneously suggest that ideological cohesion is hard to achieve during turbulent times. During political turbulence, instead, results suggest ideologically wide coalitions are more common but that minority cabinets are still more likely to appear. Despite the varying results, this analysis finds support that coalition formation is greatly affected by both economic and political turbulence. While the effects of some coalition-formation variables utilized by previous researchers appear to withstand the addition of turbulence, other effects change greatly when levels of instability are considered.

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Rahwan, Talal. « Algorithms for coalition formation in multi-agent systems ». Thesis, University of Southampton, 2007. https://eprints.soton.ac.uk/49525/.

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Coalition formation is a fundamental form of interaction that allows the creation of coherent groupings of distinct, autonomous, agents in order to efficiently achieve their individual or collective goals. Forming effective coalitions is a major research challenge in the field of multi-agent systems. Central to this endeavour is the problem of determining which of the possible coalitions to form in order to achieve some goal. This usually requires calculating a value for every possible coalition, known as the coalition value, which indicates how beneficial that coalition would be if it was formed. Now since the number of possible coalitions grows exponentially with the number of agents involved, then, instead of having a single agent calculate all these values, it would be more efficient to distribute this calculation among all agents, thus, exploiting all computational resources that are available to the system, and preventing the existence of a single point of failure. Against this background, we develop a novel algorithm for distributing the value calculation among the cooperative agents. Specifically, by using our algorithm, each agent is assigned some part of the calculation such that the agents' shares are exhaustive and disjoint. Moreover, the algorithm is decentralized, requires no communication between the agents, has minimal memory requirements, and can reflect variations in the computational speeds of the agents. To evaluate the effectiveness of our algorithm we compare it with the only other algorithm available in the literature for distributing the coalitional value calculations (due to Shehory and Kraus). This shows that for the case of 25 agents, the distribution process of our algorithm took less than 0.02% of the time, the values were calculated using 0.000006% of the memory, the calculation redundancy was reduced from 383229848 to 0, and the total number of bytes sent between the agents dropped from 1146989648 to 0. Note that for larger numbers of agents, these improvements become exponentially better. Once the coalitional values are calculated, the agents usually need to find a combination of coalitions in which every agent belongs to exactly one coalition, and by which the overall outcome of the system is maximized. This problem, which is widely known as the coalition structure generation problem, is extremely challenging due to the number of possible combinations which grows very quickly as the number of agents increases, making it impossible to go through the entire search space, even for small numbers of agents. Given this, many algorithms have been proposed to solve this problem using different techniques, ranging from dynamic programming, to integer programming, to stochastic search, all of which suffer from major limitations relating to execution time, solution quality, and memory requirements. With this in mind, we develop a novel, anytime algorithm for solving the coalition structure generation problem. Specifically, the algorithm can generate solutions by partitioning the space of all potential coalition structures into sub-spaces containing coalition structures that are similar, according to some criterion, such that these sub-spaces can be pruned by identifying their bounds. Using this representation, the algorithm can then search through the selected sub-space(s) very efficiently using a branch-and-bound technique. We empirically show that we are able to find solutions that are optimal in 0.082% of the time required by the fastest available algorithm in the literature (for 27 agents), and that is using only 33% of the memory required by that algorithm. Moreover, our algorithm is the first to be able to solve the coalition structure generation problem for numbers of agents bigger than 27 in reasonable time (less than 90 minutes for 30 agents as opposed to around 2 months for the current state of the art). The algorithm is anytime, and if interrupted before it would have normally terminated, it can still provide a solution that is guaranteed to be within a bound from the optimal one. Moreover, the guarantees we provide on the quality of the solution are significantly better than those provided by the previous state of the art algorithms designed for this purpose. For example, given 21 agents, and after only 0.0000002% of the search space has been searched, our algorithm usually guarantees that the solution quality is no worse than 91% of optimal value, while previous algorithms only guarantees 9.52%. Moreover, our guarantee usually reaches 100% after 0.0000019% of the space has been searched, while the guarantee provided by other algorithms can never go beyond 50% until the whole space has been searched. Again note that these improvements become exponentially better given larger numbers of agents.

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Riley, Luke. « Decentralised coalition formation methods for multi-agent systems ». Thesis, University of Liverpool, 2015. http://livrepository.liverpool.ac.uk/2012139/.

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Coalition formation is a process whereby agents recognise that cooperation with others can occur in a mutually beneficial manner and therefore the agents can choose appropriate temporary groups (named coalitions) to form. The benefit of each coalition can be measured by: the goals it achieves; the tasks it completes; or the utility it gains. Determining the set of coalitions that should form is difficult even in centralised cooperative circumstances due to: (a) the exponential number of different possible coalitions; (b) the ``super exponential'' number of possible sets of coalitions; and (c) the many ways in which the agents of a coalition can agree to distribute its gains between its members (if this gain can be transferred between the agents). The inherent distributed and potentially self-interested nature of multi-agent systems further complicates the coalition formation process. How to design decentralised coalition formation methods for multi-agent systems is a significant challenge and is the topic of this thesis. The desirable characteristics for these methods to have are (among others): (i) a balanced computational load between the agents; (ii) an optimal solution found with distributed knowledge; (iii) bounded communication costs; and (iv) to allow coalitions to form even when the agents disagree on their values. The coalition formation methods presented in this thesis implement one or more of these desirable characteristics. The contribution of this thesis begins with a decentralised dialogue game that utilise argumentation to allow agents to reason over and come to a conclusion on what are the best coalitions to form, when the coalitions are valued qualitatively. Next, the thesis details two decentralised algorithms that allow the agents to complete the coalition formation process in a specific coalition formation model, named characteristic function games. The first algorithm allows the coalition value calculations to be distributed between the agents of the system in an approximately equal manner using no communication, where each agent assigned to calculate the value of a coalition is included in that coalition as a member. The second algorithm allows the agents to find one of the most stable coalition formation solutions, even though each agent has only partial knowledge of the system. The final contribution of this thesis is a new coalition formation model, which allows the agents to find the expected payoff maximising coalitions to form, when each agent may disagree on the quantitative value of each coalition. This new model introduces more risk to agents valuing a coalition higher than the other agents, and so encourages pessimistic valuations.

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De, Duco Shawn Michael. « An evolution perspective of coalition formation within organizations ». CSUSB ScholarWorks, 2000. https://scholarworks.lib.csusb.edu/etd-project/1606.

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Janovsky, Pavel. « Large-scale coalition formation : application in power distribution systems ». Diss., Kansas State University, 2017. http://hdl.handle.net/2097/35328.

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Doctor of Philosophy
Department of Computing and Information Sciences
Scott A. DeLoach
Coalition formation is a key cooperative behavior of a system of multiple autonomous agents. When the capabilities of individual agents are not su fficient for the improvement of well-being of the individual agents or of the entire system, the agents can bene t by joining forces together in coalitions. Coalition formation is a technique for finding coalitions that are best fi tted to achieve individual or group goals. This is a computationally expensive task because often all combinations of agents have to be considered in order to find the best assignments of agents to coalitions. Previous research has therefore focused mainly on small-scale or otherwise restricted systems. In this thesis we study coalition formation in large-scale multi-agent systems. We propose an approach for coalition formation based on multi-agent simulation. This approach allows us to find coalitions in systems with thousands of agents. It also lets us modify behaviors of individual agents in order to better match a specific coalition formation application. Finally, our approach can consider both social welfare of the multi-agent system and well-being of individual self-interested agents. Power distribution systems are used to deliver electric energy from the transmission system to households. Because of the increased availability of distributed generation using renewable resources, push towards higher use of renewable energy, and increasing use of electric vehicles, the power distribution systems are undergoing signi ficant changes towards active consumers who participate in both supply and demand sides of the electricity market and the underlying power grid. In this thesis we address the ongoing change in power distribution systems by studying how the use of renewable energy can be increased with the help of coalition formation. We propose an approach that lets renewable generators, which face uncertainty in generation prediction, to form coalitions with energy stores, which on the other hand are always able to deliver the committed power. These coalitions help decrease the uncertainty of the power generation of renewable generators, consequently allowing the generators to increase their use of renewable energy while at the same time increasing their pro fits. Energy stores also bene t from participating in coalitions with renewable generators, because they receive payments from the generators for the availability of their power at speci fic time slots. We first study this problem assuming no physical constraints of the underlying power grid. Then we analyze how coalition formation of renewable generators and energy stores in a power grid with physical constraints impacts the state of the grid, and we propose agent behavior that leads to increase in use of renewable energy as well as maintains stability of the grid.

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Bunker, Kenneth. « Coalition formation in presidential regimes : evidence from Latin America ». Thesis, London School of Economics and Political Science (University of London), 2015. http://etheses.lse.ac.uk/3243/.

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This thesis explains coalition formation in presidential regimes with evidence from Latin America. The conventional view has been that coalition formation is considerably difficult in presidentialism, and as a result, parties have only exceptionally been expected to form coalitions. However, since the 1990s, the frequency of coalition formation has increased across the region. Most democracies have at some point elected a presidential candidate backed by an electoral coalition, or have been ruled by a president backed by a government coalition. This thesis presents three major findings that contribute to the development of a theory of coalition formation in presidential regimes. First, it shows that simple majority plurality for presidential elections, unicameralism, proportional representation, larger legislatures, smaller average district magnitudes, a higher effective number of electoral parties, and the government party’s legislative majority are crucial predictors of electoral coalition formation. It also shows that when an outsider presidential candidate is present, the likelihood of electoral coalition formation decreases. Second, this thesis shows that weak presidents elected with a low vote share are more likely to form government coalitions. It shows that simple majority plurality for presidential elections, longer presidential terms, unicameralism, smaller legislatures, and fewer legislative parties are crucial predictors of government coalition formation. It also shows that when the incumbent president was backed by an electoral coalition in the immediately previous election, or when the government is going through political turmoil, the probability of forming a government coalition increases. Third, it shows that coalitions may or may not form even when variables related to presidential power, electoral institutions, electoral systems, and party systems are not perfectly aligned. It shows that while presidential power is relevant, electoral arrangements and the party system are what ultimately determine coalition formation. While the former variable is a sufficient condition, the latter variables are both sufficient and necessary conditions. Finally, this thesis shows that political culture and critical junctures play an important role in exacerbating or ameliorating these structural incentives.

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Ahmadoun, Douae. « Interdependent task allocation via coalition formation for cooperative multi-agent systems ». Electronic Thesis or Diss., Université Paris Cité, 2022. http://www.theses.fr/2022UNIP7088.

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L'allocation des tâches à plusieurs agents autonomes devant accomplir des tâches complexes a été l'un des domaines de recherche récents sur les systèmes multi-agents. Dans de nombreuses applications, les agents sont coopératifs et doivent effectuer des tâches qui nécessitent chacune une combinaison de différentes capacités dont peut se doter un sous-ensemble d'agents. Dans ce cas, nous pouvons utiliser la formation de coalitions comme paradigme pour affecter des coalitions d'agents à des tâches. Les solutions à ce problème d'allocation de tâches, pour les systèmes robotiques en particulier, trouvent plusieurs applications dans le monde réel et prennent de plus en plus de l'importance dans les domaines de la défense, de l'espace, de la gestion des catastrophes, de l'exploration sous-marine, de la logistique, de la fabrication de produits et de l'assistance dans les services de santé. De multiples mécanismes de formation de coalitions et d'allocation de tâches ont été introduits dans l'état de l'art, tenant rarement compte des tâches interdépendantes. Cependant, il est récurrent de trouver des tâches dont la qualité ne peut être évaluée sans considérer les autres tâches dans des applications réelles. Ces tâches sont appelées interdépendantes par opposition aux tâches indépendantes qui, elles, peuvent être évaluées individuellement, ce qui entraîne une évaluation globale de l'allocation des tâches qui additionne simplement toutes les évaluations des tâches. La recherche dans le passé a conduit à de nombreuses méthodes d'allocation de tâches qui traitent le cas des tâches indépendantes sous différents angles et sous différents paradigmes. D'autres travaux résolvent le cas des tâches interdépendantes, mais ils le font soit de manière centralisée avec une complexité très élevée, soit uniquement pour le cas des dépendances de précédence. Cependant, de nombreuses formes d'interdépendance peuvent exister entre les tâches dans les applications du monde réel. Ces applications nécessitent que les mécanismes d'allocation des tâches soient décentralisés et anytime, pouvant renvoyer une solution à tout moment quitte à l'améliorer s'il reste du temps, pour répondre à des problèmes de sensibilité au temps et de robustesse. Dans cette thèse, nous considérons des environnements multi-agents coopératifs où les tâches sont multi-agents et interdépendantes, et les méthodes d'allocation des tâches doivent être décentralisées et anytime. À cet égard, nous proposons une formalisation du problème qui considère les attributs qualitatifs et quantitatifs des agents et des tâches, et qui capture les dépendances des tâches que ça soit au niveau des exigences ou au niveau de l'évaluation des allocations. Nous introduisons une nouvelle approche avec un mécanisme de formation de coalition décentralisé anytime qui permet aux agents dotés de capacités complémentaires de former, de manière autonome et dynamique, des structures de coalitions faisables qui accomplissent une tâche globale et composite. Cette approche est basée sur la formation d'une structure de coalition faisable permettant aux agents de décider quelle coalition rejoindre et donc quelle tâche accomplir afin que toutes les tâches soient faisables. Ensuite, les structures formées sont progressivement améliorées via des remplacements d'agents pour optimiser l'évaluation globale de l'allocation, le but étant d'accomplir les tâches avec les meilleures performances possibles. Nous analysons la complexité de nos algorithmes et montrons que, bien que le problème général soit NP-complet, notre mécanisme fournit une solution dans un temps acceptable. Des scénarios d'application simulés sont utilisés pour démontrer la valeur ajoutée de notre approche
Task allocation among multiple autonomous agents that must accomplish complex tasks has been one of the focusing areas of recent research in multi-agent systems. In many applications, the agents are cooperative and have to perform tasks that each requires a combination of different capabilities that a subset of agents can have. In this case, we can use coalition formation as a paradigm to assign coalitions of agents to tasks. For robotic systems, in particular, solutions to this task allocation problem have several and increasingly important real-world applications in defense, space, disaster management, underwater exploration, logistics, product manufacturing, and support in healthcare facilities support. Multiple coalition formation and task allocation mechanisms were introduced in the prior art, seldom accounting for interdependent tasks. However, it is recurrent to find tasks whose quality cannot be evaluated without considering the other tasks in real-world applications. These tasks are called interdependent in contrast to independent tasks that can be individually assessed, resulting in a global evaluation of the tasks' allocation that sums all the tasks' evaluations. Research in the past has led to many task allocation algorithms that address the case of independent tasks from different angles and under different paradigms. Other works solve the case of the interdependent tasks, but they do it either centrally with very high complexity or only for the case of precedence dependencies. However, many forms of interdependence may exist between tasks in real-world applications. In addition, these applications need task allocation mechanisms to be decentralised and available at anytime to allow them to return a solution at any time and to improve it if there is time left, to respond to their time-sensitivity and robustness issues. In this dissertation, we consider cooperative multi-agent environments where tasks are multi-agent and interdependent, and task allocation methods have to be decentralized and available at anytime. In this regard, we propose a problem formalisation that considers the agents' and the tasks' qualitative and quantitative attributes and captures the tasks' dependencies on the requirements level and the allocation evaluation level. We introduce a novel approach with a token-passing anytime decentralised coalition formation mechanism. The approach enables agents with complementary capabilities to form, autonomously and dynamically, feasible coalition structures that accomplish a global, composite task. It is based on forming a feasible coalition structure that allows the agents to decide which coalition to join and thus which task to do so that all the tasks can be feasible. Then, the formed structures are incrementally improved via agent replacements to optimise the global evaluation. The purpose is to accomplish the tasks with the best possible performance. The analysis of our algorithms' complexity shows that although the general problem is NP-complete, our mechanism provides a solution within an acceptable time. Simulated application scenarios are used to demonstrate the added value of our approach

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Präntare, Fredrik. « Simultaneous coalition formation and task assignment in a real-time strategy game ». Thesis, Linköpings universitet, Artificiell intelligens och integrerade datorsystem, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-139210.

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In this thesis we present an algorithm that is designed to improve the collaborative capabilities of agents that operate in real-time multi-agent systems. Furthermore, we study the coalition formation and task assignment problems in the context of real-time strategy games. More specifically, we design and present a novel anytime algorithm for multi-agent cooperation that efficiently solves the simultaneous coalition formation and assignment problem, in which disjoint coalitions are formed and assigned to independent tasks simultaneously. This problem, that we denote the problem of collaboration formation, is a combinatorial optimization problem that has many real-world applications, including assigning disjoint groups of workers to regions or tasks, and forming cross-functional teams aimed at solving specific problems. The algorithm's performance is evaluated using randomized artificial problems sets of varying complexity and distribution, and also using Europa Universalis 4 – a commercial strategy game in which agents need to cooperate in order to effectively achieve their goals. The agents in such games are expected to decide on actions in real-time, and it is a difficult task to coordinate them. Our algorithm, however, solves the coordination problem in a structured manner. The results from the artificial problem sets demonstrates that our algorithm efficiently solves the problem of collaboration formation, and does so by automatically discarding suboptimal parts of the search space. For instance, in the easiest artificial problem sets with 12 agents and 8 tasks, our algorithm managed to find optimal solutions after only evaluating approximately 0.000003% of the possible solutions. In the hardest of the problem sets with 12 agents and 8 tasks, our algorithm managed to find a 80% efficient solution after only evaluating approximately 0.000006% of the possible solutions.
I denna uppsats presenteras en ny algoritm som är designad för att förbättra samarbetsförmågan hos agenter som verkar i realtidssystem. Vi studerar även koalitionsbildnings- och uppgiftstilldelningsproblemen inom realtidsstrategispel, och löser dessa problem optimalt genom att utveckla en effektiv anytime-algoritm som löser det kombinerade koalitionsbildnings- och uppgiftstilldelningsproblemet, inom vilket disjunkta koalitioner formas och tilldelas uppgifter. Detta problem, som vi kallar samarbetsproblemet, är en typ av optimeringsproblem som har många viktiga motsvarigheter i verkligheten, exempelvis för skapandet av arbetsgrupper som skall lösa specifika problem, eller för att ta fram optimala tvärfunktionella team med tilldelade uppgifter. Den presenterade algoritmens prestanda utvärderas dels genom att använda simulerade problem av olika svårighetsgrad, men också genom att använda verkliga problembeskrivningar från det kommersiella strategispelet Europa Universalis 4, vilket är ett spel som agenter måste samarbeta i för att effektivt uppnå deras mål. Att koordinera agenter i sådana spel är svårt, men vår algoritm åstadkommer detta genom att systematiskt söka efter de optimala agentgrupperingarna för ett antal givna uppgifter. Resultaten från de simulerade problemen visar att vår algoritm effektivt löser samarbetsproblemet genom att systematiskt sålla bort suboptimala delar av sökrymden. I dessa tester lyckas vår algoritm generera högkvalitativa anytime-lösningar. Till exempel, i de enklaste problemen med 12 agenter och 8 uppgifter lyckas vår algoritm hitta den optimala lösningen efter det att den endast utvärderat 0.000003% av de möjliga lösningarna. I de svåraste problemen med 12 agenter och 8 uppgifter lyckas vår algoritm hitta en lösning som är 80% från den optimala lösningen efter det att den endast utvärderat 0.000006% av de möjliga samarbetsstrukturerna.

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Vries, Miranda Wilhelmina Maria de. « Governing with your closest neighbour : an assessment of spatial coalition formation theories / ». [S.l. : s.n.], 1999. http://www.gbv.de/dms/sub-hamburg/309517354.pdf.

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Namvar, Gharehshiran Omid. « Distributed dynamic coalition formation for bearings-only localization in wireless sensor networks ». Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/19003.

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Lifetime maximization is a key challenge in the design of sensor-network-based tracking applications. In this dissertation, formation of optimal coalitions of nodes is investigated for data acquisition in bearings-only target localization such that the average sleep times allocated to the nodes are maximized. Targets are assumed to be localized with a pre-defined accuracy where the determinant of the Bayesian Fisher information matrix (B-FIM) is used as the metric for estimation accuracy. Cooperative game theory is utilized as a tool to devise a distributed dynamic coalition formation algorithm in which nodes autonomously decide which coalition to join, while maximizing their feasible sleep times. Nodes in the sleep mode do not record any measurements; hence, save power in both sensing and transmitting the sensed data. The proposed scheme reduces the number of sensor measurements by capturing the spatio-temporal correlation of the information provided by the sensors from one side and bounding the localization accuracy to the pre-defined value from the other side. It is proved that if each node operates according to this algorithm, the average sleep time for the entire network converges to its maximum feasible value. In numerical examples, we illustrate the inherent trade-off between the localization accuracy and the average sleep time allocated to the nodes and demonstrate the superior performance of the proposed algorithm via Monte Carlo simulations.

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Dowell, Andrew James. « Tackling the computational complexity of understanding coalition formation in multi-agent systems ». Thesis, University of Liverpool, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.526891.

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Rodrigues, Tabajara Krausburg. « Constrained coalition formation among heterogeneous agents for the multi-agent programming contest ». Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2018. http://tede2.pucrs.br/tede2/handle/tede/8102.

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Esta disserta??o apresenta um estudo sobre forma??o de coaliz?es entre agentes heterog?neos para a competi??o de programa??o multiagente de 2017. Foi investigado e aplicado a forma??o de estruturas de coaliz?es entre agentes para resolver problemas log?sticos simulados sobre o mapa de uma cidade real. A fim de atingir o objetivo deste trabalho, foram integrados algoritmos formadores de coaliz?es na plataforma JaCaMo por meio de um artefato CArtAgO chamado CFArtefact. Foi utilizada a implementa??o provida pelo time SMART-JaCaMo (time participante da competi??o multiagente), para experimentar a forma??o de coaliz?es na competi??o. Tr?s abordagens foram avaliadas no dom?nio da competi??o em diferentes configura??es. A primeira abordagem utiliza somente aloca??o de tarefas para resolver o problema. A segunda e a terceira abordagem utilizam a t?cnica de forma??o de coaliz?es anteriormente ? aloca??o de tarefas; dentre estas abordagens, uma utiliza um algor?timo ?timo para resolver o problema e a outra um heur?stico. As an?lises dos experimentos realizados mostram que algor?timos formadores de coaliz?es podem melhorar a performance do time participante da competi??o quando a taxa de trabalhos gerados pelo simulador ? baixa. Entretanto, conforme a taxa de trabalhos aumenta, a abordagem que realiza somente aloca??o de tarefas obt?m um desempenho melhor quando comparada as demais. Mesmo a abordagem heur?stica tem desempenho pr?ximo ? abordagem ?tima para coaliz?es. Desta forma, ? poss?vel concluir que forma??o de coaliz?es possui grande valia para balancear os agentes para um conjunto de trabalhos que precisa ser completado.
This work focuses on coalition formation among heterogeneous agents for the 2017 multiagent programming contest. An agent is a computer system that is capable of independent action to achieve its goals. In order to increase the effectiveness of the agents, we can organise them into coalitions, in which the agents collaborate with each other to achieve individual or common goals. We investigate and apply coalition structure generation (the first activity of the coalition formation process) in simulated scenarios, specifically the 2017 contest scenario, where the agents forming a competing team cooperate to solve logistic problems simulated on the map of a real city. In order to achieve our goal, we integrate coalition formation algorithms into the JaCaMo platform by means of a CArtAgO artefact, named CFArtefact. We use the implementation of the SMART JaCaMo team for experimenting with the coalition formation approach in the contest scenario. We experiment on three approaches in the contest domain with different configurations. In the first, we use only a taskallocation mechanism, while the other approaches use an optimal coalition formation algorithm and a heuristic coalition formation algorithm. We conducted several experiments to compare the advantages of each approach. Our results show that coalition formation algorithms can improve the performance of a participating team when dealing with low job rates (i.e., how quickly new jobs are created by the simulation). However, as we increase the job rate, the approach using only task allocation has better performance. Even a heuristic coalition formation approach has close performance to the optimal one in that case. Coalition formation can play an important role when we aim to balance each group of agents to accomplish some particular goal given a larger team of cooperating agents.

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Vries, Miranda W. M. de. « Governing with your closest neighbour : an assessment of spatial coalition formation theories / ». Enschede : Ipskamp, 1999. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=008991203&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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Faye, Pascal François Mbissane. « Modèles de formation de coalitions stables dans un contexte ad-hoc et stochastique ». Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10062/document.

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Travailler dans un contexte ad hoc et dynamique, pour les agents, empêche : 1- l'existence d'une vue globale du système qui reflète une image complète de l'environnement de déploiement ; 2- l'existence de connaissances a priori sur la manière de se coordonner en raison de l'absence d'une structure centralisée et de la disponibilité aléatoire des entités considérés. Nous avons proposé différentes stratégies comportementales pour faciliter la stabilisation dynamique des interactions entre les agents et la convergence vers les meilleurs états de coordination. Notre conception des alliances et des recommandations permet à un agent d'évoluer de manière autonome, d'identifier dynamiquement les agents voisins fiables avec qui coopérer et de former avec son voisinage des partitions Nash-stables selon les exigences de l'environnement de déploiement. Pour répondre à la difficulté de corrélation entre les comportements locaux des agents et les propriétés de l'environnement de déploiement des agents, nous utilisons de manière originale les modèles Markoviens. Nous nous sommes aussi focalisés sur la prise en compte des interdépendances entre les agents pour augmenter leur efficacité dans un souci d'optimisation les coûts imposés aux composants ad-hoc communicants où les agents sont déployés. Cela nous a amené à proposer le modèle S-NRB (Sequentiel Non-return Broadcast) et le modèle P-NRB (Parallel Non-return Broadcast) pour la coordination distribuée qui cherchent à maximiser le bien-être social des agents. Pour mettre en exergue les propriétés intrinsèques de nos méthodes, toutes nos propositions ont été étudiées de manière théorique et expérimentale grâce à notre simulateur
An ad-hoc and stochastic context prevents : 1- the existence of a global view of the system that reflects a complete image of the deployment environment ; 2- the existence of a priori knowledge because of the lack of a centralized structure, the dynamic of the tasks and the random availability of the entities. We proposed different strategies to facilitate the dynamic stabilization of the interactions between the agents and the convergence towards better coordination states. Our conception of alliances and recommendations allows an agent to evolve independently, to dynamically identify reliable neighboring agents with whom to cooperate and to form Nash-stable or Core stable coalitions according to the requirements of the deployment environment. To face with the challenges of the correlation between local behavior of the agents and the properties of their environment, we use in an original way the Markovian models. We also focused on taking into account the interdependencies between the agents to increase their efficiency in order to optimize the imputed costs of the ad-hoc components where the agents are deployed. This led us to propose both mechanisms, the S-NRB (Sequential Non-return Broadcast) and the P-NRB (Parallel Non-return Broadcast) for distributed coordination seeking to maximize the social welfare of the agents. To highlight the intrinsic properties of our methods, our whole proposals have been studied theoretically and experimentally through our simulator

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Fremont, Gregory Benjamin Austin. « Britain's role in the formation of the third coalition against France 1802-1805 ». Thesis, University of Oxford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315852.

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Obholzer, Lukas. « Essays on bicameral coalition formation : dynamics of legislative cooperation in the European Union ». Thesis, London School of Economics and Political Science (University of London), 2014. http://etheses.lse.ac.uk/3082/.

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The thesis develops a theory of legislative cooperation in bicameral legislatures. At its core is a distinction between two decision-making scenarios leading to a concurrent majority in the two chambers. In an inter-institutional scenario, the chambers oppose each other as unitary actors. In a trans-institutional scenario, the constituent actors enter into cooperation across the boundaries of their chambers. The central argument is that formateurs face a strategic decision on which of these two routes to take. They can stick to their intra-institutional coalition, or they can abandon it and propose a logroll across issues within a bill that is carried by a majority across the chambers. The thesis comprises three papers, united by the general topic of trans-institutional legislative cooperation, and each demonstrating the crucial role of the formateurs. The empirical analysis focuses on co-decision legislation proposed in the bicameral system of the European Union between 1999 and 2009. In particular, it draws on a new dataset on early-stage and final-stage coalitions in the European Parliament and the Council of the EU. This is based on an extensive analysis of more than 18,000 Council documents and 19,000 amendments in the EP presenting for the first time a systematic insight into early-stage coalitions. Three central findings emanate from the application of the theoretical framework to the new data. First, formateurs can obtain an outcome closer to their preferences by choosing between inter- and trans-institutional scenarios. Second, the transaction costs of exchanges across institutional boundaries are lower if formateurs’ preferences are similar. Third, the decisions of the formateurs potentially produce winners and losers as some actors are included and others are excluded from the coalitions. These findings build on and further develop theories of bicameral coalition formation and legislative organisation. They highlight that the strategic environment in which actors operate surpasses their individual chamber, and explain how this affects the process and outcome of decision-making. This leads to important empirical and theoretical contributions which raise normative implications.

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Wagner, Lisa [Verfasser], Martin Akademischer Betreuer] Hoefer et Peter [Akademischer Betreuer] [Rossmanith. « Matching and coalition formation in uncoordinated markets / Lisa Wagner ; Martin Hoefer, Peter Rossmanith ». Aachen : Universitätsbibliothek der RWTH Aachen, 2015. http://d-nb.info/1126278386/34.

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Wagner, Lisa Verfasser], Martin [Akademischer Betreuer] Hoefer et Peter [Akademischer Betreuer] [Rossmanith. « Matching and coalition formation in uncoordinated markets / Lisa Wagner ; Martin Hoefer, Peter Rossmanith ». Aachen : Universitätsbibliothek der RWTH Aachen, 2015. http://d-nb.info/1126278386/34.

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Ballester, Pla Coralio. « On Peer Networks and Group Formation ». Doctoral thesis, Universitat Autònoma de Barcelona, 2005. http://hdl.handle.net/10803/4064.

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En el artículo "NP-completeness in Hedonic Games", identificamos algunas limitaciones significativas de los modelos estándar de juegos cooperativos: A menudo, es imposible alcanzar una organización estable de una sociedad en una cantidad de tiempo razonable. Las implicaciones básicas de estos resultados son las siguientes, Primero, desde un punto de vista positivo, las sociedades están "condenadas" a evolucionar constantemente, más que a alcanzar un estadio de equilibrio en el corto plazo. Segundo, desde una perspectiva normativa, un hipotético organizador de la sociedad debería tomar en consideración las limitaciones prácticas de tiempo a la hora de implementar un orden social estable.
Para obtener nuestros resultados, utilizamos el concepto de NP-completitud, que es un modelo bien establecido de complejidad temporal en Ciencias de la Computación. En concreto, nos concentramos en estabilidad grupal y estabilidad individual en juegos hedónicos. Los juegos hedónicos son una clase simple de juegos cooperativos en los que la utilidad de cada individuo viene totalmente determinada por el grupo laboral al que pertenece. Nuestros resultados referentes a la complejidad, expresados en términos de NP-completitud, cubren un amplio espectro de dominios de las preferencias individuales, incluyendo preferencias estrictas, indiferencias en las preferencias o preferencias libres sobre el tamaño de los grupos. Dichos resultados también se cumplen si nos restringimos al caso en el que el tamaño máximo de los grupos es pequeño (dos o tres jugadores)
En el artículo "Who is Who in Networks. Wanted: The Key Player" (junto con Antoni Calvó Armengol e Yves Zenou), analizamos un modelo de efectos de grupo en el que los agentes interactúan en un juego de influencias bilaterales. Los juegos no cooperativos con población finita y utilidades linales-cuadráticas, en los cuales cada jugador decide cuánto esfuerzo ejercer, pueden ser interpretados como juegos en red con complementariedades en los pagos, junto con un componente de susitucion global y uniforme, y un efecto de concavidad propia.
Para dichos juegos, la acción de cada jugador en un equilibrio de Nash es proporcional a su centralidad de Bonacich en la red de complementariedades, estableciendo así un puente con la literatura de redes sociales. Dicho vínculo entre Bonacich y Nash implica que el equilibrio agregado aumenta con el tamaño y la densidad de la red.
También analizamos una política que consiste en seleccionar al jugador clave, ésto es, el jugador que, una vez eliminado del juego, induce un cambio óptimo en la actividad agregada. Proveemos una caracterización geométrica del jugador clave, identificada con una medida de inter-centralidad, la cual toma en cuenta tanto la centralidad de cada jugador como su contribución a la centralidad de los otros.
En el artículo "Optimal Targets in Peer Networks" (junto con Antoni Calvó Armengol e Yves Zenou), nos centramos en las consecuencias y limitaciones prácticas que se derivan del modelo de decisiones sobre delincuencia. Las principales metas que aborda el trabajo son las siguientes. Primero, la elección se extiende el concepto de delincuente clave en una red al de grupo clave. En dicha situación se trata de seleccionar de modo óptimo al conjunto de delincuentes a eliminar/neutralizar, dadas las restricciones presupuestarias para aplicar medidas. Dicho problema presenta una inherente complejidad computacional que solo puede salvarse mediante el uso de procedimientos aproximados, "voraces" o probabilísticos. Por otro lado, tratamos el problema del delincuente clave en el contexto de redes dinámicas, en las que, inicialmente, los individuos deciden acerca de su futuro como delincuentes o como ciudadanos que obtienen un salario fijo en el mercado. En dicha situación, la elección del delincuente clave es más compleja, ya que el objetivo de disminuir la delincuencia debe tener en cuenta los efectos en cadena que pueda traer consigo la desaparición de uno o varios delincuentes. Por último, estudiamos la complejidad computacional del problema de elección óptima y explotamos la propiedad de submodularidad de la intercentralidad de grupo, lo cual nos permite acotar el error relativo de la aproximación basada en un algoritmo voraz.
The aim of this thesis work is to contribute to the analysis of the interaction of agents in social networks and groups.
In the chapter "NP-completeness in Hedonic Games", we identify some significant limitations in standard models of cooperation in games: It is often impossible to achieve a stable organization of a society in a reasonable amount of time. The main implications of these results are the following. First, from a positive point of view, societies are bound to evolve permanently, rather than reach a steady state configuration rapidly. Second, from a normative perspective, a planner should take into account practical time limitations in order to implement a stable social order.
In order to obtain our results, we use the notion of NP-completeness, a well-established model of time complexity in Computer Science. In particular, we concentrate on group stability and individual stability in hedonic games. Hedonic games are a simple class of cooperative games in which each individual's utility is entirely determined by her group. Our complexity results, phrased in terms of NP-completeness, cover a wide spectrum of preference domains, including strict preferences, indifference in preferences or undemanding preferences over sizes of groups. They also hold if we restrict the maximum size of groups to be very small (two or three players).
The last two chapters deal with the interaction of agents in the social setting. It focuses on games played by agents who interact among them. The actions of each player generate consequences that spread to all other players throughout a complex pattern of bilateral influences.
In "Who is Who in Networks. Wanted: The Key Player" (joint with Antoni Calvó-Armengol and Yves Zenou), we analyze a model peer effects where agents interact in a game of bilateral influences. Finite population non-cooperative games with linear-quadratic utilities, where each player decides how much action she exerts, can be interpreted as a network game with local payoff complementarities, together with a globally uniform payoff substitutability component and an own-concavity effect.
For these games, the Nash equilibrium action of each player is proportional to her Bonacich centrality in the network of local complementarities, thus establishing a bridge with the sociology literature on social networks. This Bonacich-Nash linkage implies that aggregate equilibrium increases with network size and density. We then analyze a policy that consists in targeting the key player, that is, the player who, once removed, leads to the optimal change in aggregate activity. We provide a geometric characterization of the key player identified with an inter-centrality measure, which takes into account both a player's centrality and her contribution to the centrality of the others.
Finally, in the last chapter, "Optimal Targets in Peer Networks" (joint with Antoni Calvó-Armengol and Yves Zenou), we analyze the previous model in depth and study the properties and the applicability of network design policies.
In particular, the key group is the optimal choice for a planner who wishes to maximally reduce aggregate activity. We show that this problem is computationally hard and that a simple greedy algorithm used for maximizing submodular set functions can be used to find an approximation. We also endogeneize the participation in the game and describe some of the properties of the key group. The use of greedy heuristics can be extended to other related problems, like the removal or addition of new links in the network.

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Beer, Sebastian Verfasser], Michael [Akademischer Betreuer] [Sonnenschein, Jürgen [Akademischer Betreuer] Sauer et Sascha [Akademischer Betreuer] Ossowski. « Dynamic coalition formation in electricity markets / Sebastian Beer ; Michael Sonnenschein, Jürgen Sauer, Sascha Ossowski ». Oldenburg : BIS der Universität Oldenburg, 2016. http://d-nb.info/1148644679/34.

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Beer, Sebastian Verfasser], Michael [Akademischer Betreuer] Sonnenschein, Jürgen [Akademischer Betreuer] [Sauer et Sascha [Akademischer Betreuer] Ossowski. « Dynamic coalition formation in electricity markets / Sebastian Beer ; Michael Sonnenschein, Jürgen Sauer, Sascha Ossowski ». Oldenburg : BIS der Universität Oldenburg, 2016. http://d-nb.info/1148644679/34.

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Tobias, Jutta M. « "Best buddy taking on big daddy" : factors affecting coalition formation between in- & ; out-group members ». Online access for everyone, 2006. http://www.dissertations.wsu.edu/Thesis/Summer2006/j%5Ftobias%5F053006.pdf.

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Blankenburg, Bastian [Verfasser], et Matthias [Akademischer Betreuer] Klusch. « Coalition formation among rational agents in uncertain and untrustworthy environments / Bastian Blankenburg. Betreuer : Matthias Klusch ». Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2014. http://d-nb.info/1053980671/34.

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Bergman, Torbjörn. « Constitutional rules and party goals in coalition formation : an analysis of winning minority governments in Sweden ». Doctoral thesis, Umeå universitet, Statsvetenskapliga institutionen, 1995. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-8665.

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This study starts with two theoretical puzzles within the rational choice oriented literature on government formation in parliamentary democracies: the relative importance of constitutional rules and the existence of multiple party goals. From these puzzles stem the research questions that guide the study: First, what is the theoretical and empirical link between constitutional arrangements (including rules) and party goals? Second, what are the goals of political parties and how can these be studied? Third, relative to the goals of political parties and other constitutional arrangements, what is the importance of government formation rules for the empirical record of minority and majority governments?Coalition theory provides the theoretical starting point from which the research questions stem. The historical-institutional strand of new institutionalism is used to guide the general understanding of the importance of institutional context. The rational choice oriented strand is used for a detailed study of the design of the Swedish government formation rules and an analysis of how the formation rules affect the goal seeking (micro-logic) of actors.Based on both cross-national data and an in-depth study of Swedish coalition and government formation, the analysis shows that the answer to research question number one is that the link between constitutional arrangements and party goals is one of co-determination. The answer to research question number two is that party leaders pursue four main goals and that this should be an explicit model assumption. The answer to research question number three is that the government formation rules help determine the parties' bargaining positions and for that reason they are of significant importance for the formation of minority and majority governments.
digitalisering@umu

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Spradling, Matthew. « Role Based Hedonic Games ». UKnowledge, 2015. http://uknowledge.uky.edu/cs_etds/38.

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In the hedonic coalition formation game model Roles Based Hedonic Games (RBHG), agents view teams as compositions of available roles. An agent's utility for a partition is based upon which role she fulfills within the coalition and which additional roles are being fulfilled within the coalition. I consider optimization and stability problems for settings with variable power on the part of the central authority and on the part of the agents. I prove several of these problems to be NP-complete or coNP-complete. I introduce heuristic methods for approximating solutions for a variety of these hard problems. I validate heuristics on real-world data scraped from League of Legends games.

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Chan, Nicholas. « The construction of the South : developing countries, coalition formation and the UN climate change negotiations, 1988-2012 ». Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:3478cbf5-e564-424f-a0f6-171a9e25e083.

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The North-South divide is one of the central political characteristics of the UN climate change negotiations. But while the Group of 77 coalition has been the main negotiating group for the South, developing countries have often faced challenges to their unity, magnified by the recent establishment of smaller negotiating groups. How has 'the South' hung together? This thesis investigates how developing countries have formed negotiating groups over the two decades of the UN climate negotiating process. It explains the origins of the different negotiating groups that have formed over this time, as well as the timing of their emergence and the scope of their membership. In particular, while scholarly attention has focused on the G77, Alliance of Small Island States (AOSIS) and most recently the Brazil-South Africa- India-China (BASIC) coalition, this thesis corrects the relative neglect in understanding the many other negotiating groups that have formed. While conventional explanations highlights the shared material interests that underpin group formation, this thesis advances a constructivist argument that emphasises instead the importance of collective identities in shaping norms of 'appropriate association' – the social bases of whose one's friends and allies are. It highlights the regional basis for many of these negotiating groups that cut across shared material circumstances, and draws upon historical institutionalist insights on critical junctures and path dependence to place this larger pattern of Southern coalition formation in the appropriate historical and institutional context of the UN system. It demonstrates the continuing persistence of countries identifying as the 'South', where despite changing material circumstances and disagreements among developing countries, the salience of the G77 as the constitutive institution of this identity remains. Above all, in investigating the processes of coalition formation among developing countries in the climate context, this thesis deepens scholarly understanding about the contemporary meaning of the 'South'.

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Kučera, Tomáš. « Formování multiagentních koalic pomocí genetických algoritmů ». Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2019. http://www.nusl.cz/ntk/nusl-403212.

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This thesis discusses the basics of software agents and the way they form the multiagent coalitions. Genetic algorithms are introduced as one of the methods of solving the coalition formation problem. MAPC 2018 competition is introduced, which inspired the final design and implementation of the solution by using the tools described. A demo project was created, in which agents communicate with the MASSim server and gather data which is then used as an input into the genetic algorithm. Its purpose is to assign the agents to the tasks based on the input data, so that the tasks can be accomplished in the most effective manner possible. The results of this algorithm are evaluated in experiments which are focused on the quality of the solutions found as well as the time required for the calculation.

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Siggelkow, Benjamin Florian [Verfasser]. « Coordination Issues in Tax Competition : Essays on the Relief of Double Taxation and on Coalition Formation / Benjamin Florian Siggelkow ». Hagen : Fernuniversität Hagen, 2016. http://d-nb.info/1118511301/34.

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Fritz, Alarik M. « How superpowers go to war and why other states help them the impact of asymmetric security interdependence on war coalition formation / ». Connect to Electronic Thesis (ProQuest) Connect to Electronic Thesis (CONTENTdm), 2008. http://worldcat.org/oclc/453941583/viewonline.

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Pan, Chen-Yu. « Essays on Public Economics and Political Economy ». Thesis, Boston College, 2014. http://hdl.handle.net/2345/bc-ir:103745.

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Thesis advisor: Hideo Konishi
My doctoral dissertation consists of three chapters on political economy and public economics. The first chapter discusses the effect of media bias on a voting competition. The second chapter focuses on how residents respond to increasing natural disaster risks in a multi-community framework. The third chapter investigates a coalition formation game with congestion effects. In chapter 1, I present a two-party election model with media noise. The media may provide polarized messages instead of those that explain the parties' actual policies. The rational voter relies on the media as an imperfect information source regarding a party's platform. Given this framework, I show that Downsian policy convergence is not valid. Moreover, when a party's ideology is relatively strong and the media bias is significant, one-sided polarization can occur: the party with more imprecise reports may adopt a more extreme strategy, whereas its opponent is more of a centrist in a perfect Bayesian equilibrium. This occurs when one party is misrepresented more often, causing the voter to think that the other party has more incentive to polarize. Therefore, the voter may favor the highly misrepresented party, which gives that party more room to polarize. I also show that parties never gain from these increasing misrepresentations, and a biased media environment can negatively affect the voter's welfare. My results suggest that the public should pursue a balanced media environment. Global warming and climate change have become increasingly important. In chapter 2, I investigate a local public goods economy using a new element: location-specific risks of disasters. Agents in this economy ``vote with their feet'' by choosing their favorite location as their residential base. In each location, all residents use majority rule to decide the local wealth tax rate and the amount of local public goods provision that can reduce the loss caused by disasters. I show that the equilibrium is wealth stratified if preferences are represented by a homothetic Stone-Geary utility function. Moreover, when disaster risks at a location increase, the population usually moves away from that location and the housing rents consequently decrease. Meanwhile, the housing rents and tax rates increase at the location the residents shift to. Moreover, I use this framework to numerically evaluate two policies: foreign donation and inter-jurisdiction transfer. If developed countries provides subsidies to a location with greater risks in a developing country, wealthier agents in the recipient country may move into the said location and force poorer agents to move out. This effect makes the wealthier the direct beneficiary of the foreign subsidy. Furthermore, I find that the inter-jurisdiction transfer may harm the poorer by rising housing rents. In chapter 3, I consider a coalition-formation problem, in which there is a set of feasible alternatives for each coalition and each player's payoff is affected by the coalition she belongs to and by its chosen alternative. In this chapter, I focus on ``congestion effects'': an agent's payoff goes down as an additional player joins the coalition other things being equal. The equilibrium notion considered is ``stability": a stable allocation (pairs of coalition structure and alternatives chosen by each coalition) is an allocation such that no coalition has an incentive to deviate from it. I find quite robust counterexamples to show that stability may fail to exist even under strong preference conditions such as the intermediate preference property and single peakedness. Nevertheless, I show a sufficient condition for the nonemptiness of stability: congruent-pair solvability. I also provide some results on the ``Nash-like" equilibrium notion
Thesis (PhD) — Boston College, 2014
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Economics

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Petter, Lundqvist. « Sverigedemokraterna och svenska kommunstyren : Ett pariapartis politiska påverkan ». Thesis, Uppsala universitet, Statsvetenskapliga institutionen, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-392219.

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The Pariah Party Influence on Local Government Formation in Swedish Municipalities 2002-2018 This paper studies the correlation between the rise of the radical right party The Sweden Democrats and the rise of minority governments and bloc transcending/cross-partisan coalitions in Swedish local governments; the role of the Sweden Democrats in this development is studied and further its impact in the relation between right/left-wing governments. Taking off in classical coalition- and government formation theory together with the concept of pariah parties, I also continue to discuss the setting of local government in Sweden and its implication on local government studies in general. Regression analysis of formed government in the 290 Swedish municipalities over the last five local elections, 2002-2018, is used to answer the question of how the pariah party that is the Sweden Democrats, have affected the types of local government in Sweden. The study finds that the rise of the Sweden Democrats in Swedish municipal parliaments to a large extent can explain both an increase of cross-partisan coalitions and of minority governments. This can however only be said when the party holds the balance of power; just the size or sheer presence of the party in local parliaments does not seem to have a significant impact on government type. When the party does hold the power of balance, one can observe a significant shift in favour of right-wing governments over left-wing governments. Albeit not participating in government and being considered a pariah party, or perhaps because of this fact, the rise of the Sweden Democrats has significantly affected the character of Swedish local governments.

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Ormerod, Gerald J. « Advocacy Coalition Formation, Mobilization, Sustainment, and Fragmentation : A Case Study of the New Orleans Federal Alliance (NOFA) and the Federal City Project ». ScholarWorks@UNO, 2016. http://scholarworks.uno.edu/td/2266.

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U.S. military bases and installations represent trillions of dollars of capital investment towards the nation’s defense infrastructure. The Department of Defense, in its response to the end of the Cold War with the Soviet Union in the 1980s, sought to reorganize and optimize this basing infrastructure to meet the emerging threats of the 21st century. A series of nationwide Base Realignment and Closure (BRAC) efforts were chartered by Congress to facilitate this task, identifying hundreds of obsolete or unneeded military installations. During the last BRAC effort in 2005, the Naval Support Activity New Orleans was targeted for closure, with its U.S. Navy and Marine Corps tenants to be reassigned elsewhere. In response to this threat, a group of retired military and civilian elites formed a non-profit entity known as the New Orleans Federal Alliance (NOFA), chartered to lobby the BRAC Commission to salvage the West Bank portion of the NSA from closure and establish a new mixed use, public-private Federal City complex in its stead. The purpose of this study was to examine the life cycle of NOFA and its partners in the context of the Federal City project over a ten year period. Interviews of key personnel involved with this coalition revealed remarkable insight into the characteristics associated with its formation, mobilization, sustainment, and fragmentation. The data illustrated the delicate relationship between the military history of New Orleans and its unique culture, and how that culture influenced actor behavior through the varied governing subsystems in the region. As one would expect, local politics dominated the adverse dynamic of the coalition’s solvency, heightened significantly in national visibility by the effects of Hurricane Katrina. The result was the dissolution of the NOFA-centered coalition and the failure of the Federal City project to achieve full maturity.

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Vosooghi, Sareh. « Three essays on information and transboundary problems in environmental and resource economics ». Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/22867.

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The thesis contains three chapters on environmental and natural resource economics and focuses on situations where agents receive private or public information. The first chapter analyses the problem of transboundary fisheries, where harvesting countries behave non-cooperatively. In addition to biological uncertainty, countries may face strategic uncertainty. A country that receives negative assessments about the current level of the fish stock, may become “pessimistic” about the assessment of the other harvesting country, which can ignite “panic-based” overfishing. In such a coordination problem, multiplicity of equilibria is a generic characteristic of the solution. Both strategic uncertainty and equilibrium selection, relatively, have been given less attention in the theoretical literature of common-property natural resources. In this model, in the limit as the harvesting countries observe more and more precise information, rationality ensures the unique “global game” equilibrium, a la Carlsson and van Damme (1993). The improved predictive power of the model helps a potential intergovernmental manager of the stock understand the threshold behaviour of harvesting countries. The global game threshold coincides with the risk-dominance threshold of a precise information model, as if there was no strategic uncertainty, and implies that the countries select the corresponding risk-dominant action for any level of assessment of the stock. Gaining from the risk-dominance equivalence, I derive policy suggestions for the overfishing cost and the property rights in common-property fisheries. The second chapter develops a theoretical framework to examine the role of public information in dynamic self-enforcing international environmental agreements (IEAs) on climate change. The countries choose self-enforcing emission abatement strategies in an infinite-horizon repeated game. In a stochastic model, where the social cost of greenhouse gasses (GHG) is a random variable, a central authority, as an information sender, can control release of information about the unknown state to the countries. In the literature on stochastic IEAs, it is shown that comparison of different scenarios of learning by the countries, depends on ex-ante difference of true social cost of GHG from the prior belief of countries. Here, I try to understand, in a signalling game between the informed sender and the countries, whether the no-learning or imperfect-learning scenarios, can be an equilibrium outcome. It is shown that the equilibrium strategy of the sender, who is constrained to a specific randomisation device and tries to induce an incentive-compatible abatement level which is Pareto superior, leads to full learning of social cost of GHG of symmetric and asymmetric countries. Finally, in the third chapter, I again examine a setting, where a central authority, as an information sender, conducts research on the true social cost of climate change, and releases information to the countries. However, in this chapter, instead of restricting the sender to a specific signalling structure, the sender, who has commitment power, by designing an information mechanism (a set of signals and a probability distribution over them), maximises his payoff, which depends on the mitigation action of countries and the social cost of green-house gases(GHG). The countries, given the information policy (the probability distribution over signals) and the public signal, update their beliefs about the social cost of GHG and take a mitigation action. I derive the optimal information mechanism from the general set of public information mechanisms, in coalition formation games. I show that the coalition size, as a function of beliefs, is an endogenous variable, induced by the information sender. If the sender maximises the expected payoff of either of non-signatories or signatories of the climate treaty, then full revelation is the optimal information policy, while if the sender attempts to reduce the global level of GHG, then optimal information policy leads to imperfect disclosure of the social cost. Furthermore, given any of the specifications of the sender’s payoff, the optimal information policy leads to the socially optimal mitigation and membership outcomes.

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Levando, Dmitry <1966&gt. « Essays on trade and cooperation ». Doctoral thesis, Università Ca' Foscari Venezia, 2012. http://hdl.handle.net/10579/1177.

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In this dissertation, we study two questions of strategic behavior. One is related to the trade in strategic market games. The paper studies strategic market games with wash sales. This class of games posses best response correspondences that in turn generate non-uniqueness of pure strategy equilibria. We introduce a mixed strategy equilibrium that resolves the aforementioned indeterminacy, therefore, results into a unique equilibrium. Finally we provide an example that illustrates our equilibrium concept. Another paper offers non-cooperative mechanism for coalition formation. It includes a special non-cooperative game and a self-financed enforcement. Enforcement is performed by an external central planner. The enforcement operates as a reallocation between all players in the game. In order to support stability of the induced coalition partition the central planner distorts payoffs in an equilibrium ("a carrot") and outside the equilibrium ("a stick"). Induced cores of the distorted game can not exist without the enforcement. If the enforcement exists, then the corresponding induced equilibrium has the properties of a strong Nash equilibrium. Credibility of the enforcement is supported by the balance of used resources from one side and reallocations and punishments from another.

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Arib, Souhila. « Mécanismes de formation de coalitions d’agents dans les processus de planification ». Thesis, Paris 9, 2015. http://www.theses.fr/2015PA090027.

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Le travail que nous présentons dans cette thèse s'articule autour du problème de la formation de coalitions entre des agents égoïstes qui planifient leurs activités, dans les systèmes multi-agents (SMA). Nous avons proposé, dans un premier temps, un mécanisme qui se fonde sur l’analyse des actions des agents dans leurs plans et le raisonnement sur les plans des autres, grâce notamment au calcul d’un degré de croyance sur les actions. Nous nous sommes, par ailleurs, intéressés au problème de la formation de coalitions avec des contraintes dynamiques et des préférences que les agents révèlent et communiquent aux autres lors de leurs négociations. Enfin, nous avons affiné notre mécanisme de formation des coalitions en permettant une recherche des coalitions guidée par la construction d'un arbre de contraintes et d'un arbre de coalitions, qui sont ensuite exploré par le biais de l'algorithme Monte-Carlo
The work we present, in this thesis, focuses on the coalition formation problem for self-interested agents which plan their activities in multi-agents systems. As a first step, we have proposed, a mechanism that is based on the analysis of the agents' actions in their plans and reasoning about the plans of others. Additionally, we have addressed the problem of coalition formation with dynamic constraints and preferences that agents reveal and communicate to others during their negotiations. Finally, we have refined our coalition formation mechanism allowing a guided search of the coalitions by building a tree of constraints and a tree of coalitions. Each tree is explored by means of the Monte-Carlo algorithm

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Cara, Frank Araujo de Abreu. « Uma heurística ganha-ganha para formação de coalizões em sistemas multiagentes ». Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/3/3142/tde-26122013-145159/.

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Sistemas multiagentes muitas vezes apresentam características que os aproximam de sociedades de agentes e, como as humanas, possuem normas e organizações com o objetivo de coordenar as interações entre os seus membros. Coalizão é um tipo de estrutura organizacional temporária, montada com objetivos específicos. A teoria dos jogos estuda formalmente o fenômeno coalizional, se detendo em demonstrações de propriedades e características dessa estrutura. A área de sistemas multiagentes, por outro lado, tem mostrado significativo interesse nas estruturas coalizionais como forma de organizar a cooperação entre os agentes, dedicando-se ao desenvolvimento de algoritmos para formação de coalizões. Esse trabalho apresenta um algoritmo de formação de coalizões para compartilhamento de recursos, denominado heurística ganha-ganha. Definimos um modelo que utiliza a abstração de recursos para representar tanto a posse de habilidades e objetos, quanto para representar os objetivos dos agentes. Um jogo de votação k-ponderado é utilizado para implementar o processo decisório de quais coalizões são válidas e o algoritmo testa iterativamente cada vizinhança de um agente na busca de associações vantajosas. Demonstramos que o algoritmo incrementa monotonicamente o bem-estar da sociedade e converge para uma estrutura coalizional. Também mostramos empiricamente que a heurística é eficiente para compartilhamento de recursos em situações de abundância de recursos, montando coalizões em poucas iterações e com uma quantidade grande de agentes.
Multiagent systems frequently show characteristics that come closer to agent societies and, like the humans ones, have norms and organizations in order to coordinate the interactions of its members. Coalition is a type of temporary organizational structure, assembled with specific goals. Game theory formally studies the coalitional phenomenon focusing in the demonstrations of properties and characteristics of this structure. The area of multiagent systems, on the other hand, has devoted significant interest in coalition structures as a way to organize cooperation between its members, and has been dedicated to the development of algorithms for coalition formation. This dissertation presents an algorithm to coalition formation named win-win heuristic. We define a model which uses the abstraction of resources to represent either, the possession of abilities and objects, or to represent the agents target. A k-weight voting game is used to implement the decision process of what coalitions are worth and an iteratively algorithm tests each agent neighborhood in the pursue of better associations. We demonstrate that the algorithm monotonically increases the society welfare and converges to a coalitional structure. We also show empirically that the heuristic is efficient for resource sharing in situations of availability of resources, building coalitions with few iterations and a large amount of agents.

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Blomqvist, Fredrik. « FÖRESTÄLLNINGAR OCH INTRESSEN : En fallstudie utifrån Advocacy Coalition Framework av en lokal policyprocess om expropriation ». Thesis, Uppsala universitet, Statsvetenskapliga institutionen, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-274988.

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This paper examines the viability of the Advocacy Coalition Framework(ACF) by applying it in a single case study. The aim is to advance the framework’s theoretical understanding of the policy process and its usefulness for analyzing local policy contexts. The case addressed is a long-spun policy conflict regarding the use of compulsory acquisition of real estate by a Swedish municipality for the sake of local business development. Analyzed data consisted of the municipality diary on the issue, correspondence between actors, public statements, official and internal documents and interviews with actors and non-actors. The ACF is a good starting point for understanding this local policy process, largely because of the great flexibility of its concepts. However, its basic assumptions on beliefs cannot fully explain observed events. Relating to this, the paper has five main findings. First, although beliefs play an important role in forming policy action, so does interests. Second, a conjunction of beliefs and self-interest is an important condition for some actors’ actions. Third, coalition formation is not dependent on similarity of beliefs but on similarity of policy objectives. Fourth, policy objectives are resultant of beliefs for some actors, of self-interest for others and for yet others the result of both. Therefore, actors in coalition act to achieve the same policy objectives but not necessarily for the same reasons. Fifth, one non-actor refrained from policy action in spite of strong policy core beliefs due to the policy process not being a zero sum game for this non-actor. This paper supports recent studies proposing the incorporation of interests into the ACF. For further development of the ACF the paper suggests further research to answer two generic questions: What is the relationship betweeninterests and beliefs? Are potential actors more likely to take policy action inzero sum game policy processes? For the ACF to cope with certain conditionsin local contexts the paper suggest further research into the question: Is the level of abstraction of policy issues key in understanding the involvement of legal and natural persons and their basis for policy action?

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Louati, Amine. « Une approche multi-agents pour la composition de services Web fondée sur la confiance et les réseaux sociaux ». Thesis, Paris 9, 2015. http://www.theses.fr/2015PA090035/document.

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Dans cette thèse, nous nous intéressons aux problèmes de découverte, de sélection et de composition de services. L'objectif est de satisfaire une requête complexe d'un demandeur de services. Pour ce faire, nous proposons une approche multi-agents fondée sur la confiance et les réseaux sociaux. Nous définissions un modèle de confiance en tant que concept compositionnel formé de quatre composantes: une composante sociale, une composante d'expertise, une composante de recommandation et une composante de coopération. La composante sociale juge s'il est intéressant de suivre un fournisseur avant d'utiliser ses services. La composante d'expertise estime si un service se comporte bien et comme prévu. La composante de recommandation vérifie si un agent est pertinent ou pas et si l'on peut compter sur ses recommandations. La composante de coopération permet aux agents de décider avec qui interagir dans une composition de services. Nous proposons un algorithme distribué pour la découverte de services utilisant la confiance entre les agents ainsi que les systèmes de références dans les réseaux sociaux. Nous développons également une nouvelle méthode s'appuyant sur un modèle probabiliste pour inférer la confiance entre les agents non adjacents tout en tenant compte des rôles des agents intermédiaires. Finalement, nous présentons un processus original de formation de coalitions qui est incrémental, dynamique et recouvrant pour une composition de services dans les réseaux sociaux. Les résultats expérimentaux montrent que nos approches multi-agents sont efficaces, plus performants que les approches similaires existantes et peuvent offrir des résultats plus dignes de confiance à faible coût de communications
This thesis deals with service discovery, selection and composition problems. The aim is to fulfill a complex requester query. To do that, we propose a multi-agent approach based on trust and social networks. We define a trust model as a compositional concept that includes social, expert, recommender and cooperation-based component. The social-based component judges whether or not the provider is worthwhile pursuing before using his services. The expert-based component estimates whether or not the service behaves well and as expected. The recommender-based component checks whether or not an agent is reliable and if we can rely on its recommendations. The cooperation-based component allows agents to decide with whom to interact in a service composition. We propose a distributed algorithm for service discovery using trust between agents and referral systems in social networks. We also develop a new method based on a probabilistic model to infer trust between non adjacent agents while taking into account roles of intermediate agents. Finally, we present an original coalition formation process which is incremental, dynamic and overlapping for service composition in social networks. %In particular, our coalition formation process engaging self-interested agents is incremental, dynamic and overlapping. Experimental results show that our multi-agents approaches are efficient, outperforms existing similar ones and can deliver more trustworthy results at low cost of communications

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Hagen, Achim. « Global Climate Policy Beyond Nation-State Actors ». Doctoral thesis, Humboldt-Universität zu Berlin, 2018. http://dx.doi.org/10.18452/19547.

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Internationale Kooperation zur Vermeidung von gefährlichem anthropogenen Klimawandel erweist sich als sehr komplex. Viele Schwierigkeiten, ein verbindliches internationales Abkommen mit ausreichenden Reduktionszielen zu erreichen, sind augenscheinlich und werden in bestehender ökonomischer Literatur ausführlich diskutiert. Es entstehen allerdings stetig neue Ansätze und Ideen um Klimakooperation zu fördern. Diese Arbeit untersucht neue Wege der internationalen Klimakooperation und erweitert den Horizont der spieltheoretischen Forschung zu internationalen Umweltabkommen um Ansätze aus der Global Governance, politischen Ökonomie und Außenhandelspolitik. Zudem wird die Übertragbarkeit spieltheoretischer Erkenntnisse aus der Forschung zum Klimaschutz für die transnationale Klimaanpassung diskutiert. Die Arbeit fundiert in großen Teilen auf analytisch-spieltheoretischer Modellierung. In der zu Grunde liegenden Spielstruktur entscheiden Länder anfangs, ob sie einer internationalen Koalition beitreten oder nicht. Anschließend wählen die Koalitionsmitglieder ihr Emissionsniveau in einem Spiel zwischen der Koalition und den Nichmitgliedern. In diesem Analyserahmen wird die Option mehrerer gleichzeitig parallel existierender Klimaklubs auf ihr Potenzial zur Verbesserung der Zusammenarbeit und Emissionsminderung untersucht. Darüber hinaus wird der Einfluss von politischen Interessengruppen (Lobbys), die die Interessen von Industrie und Umweltverbänden vertreten, auf die Stabilität internationaler Umweltabkommen analysiert. Dies geschieht durch eine politökonomische Ergänzung des Grundmodells. Die Eignung von Handelssanktionen als Mittel zur Förderung der internationalen Kooperation für den Klimaschutz wird ebenfalls in einem analytischen Model untersucht und die Auswirkungen dieser Maßnahmen anschließend in einem angewandten allgemeinen Gleichgewichtsmodell quantifiziert.
International cooperation to avoid dangerous anthropogenic climate change has proven to be very hard to achieve. The difficulties to reach a binding international agreement with sufficient reduction targets are evident and extensively discussed in the economic literature. Nevertheless, new ideas towards cooperation are evolving. This thesis offers an exploration of new avenues to international climate cooperation, widening the scope of game theoretic research on international environmental agreements towards global governance literature, political economy and trade. It also extends the potential applicability of the findings from the game theoretic literature on international environmental agreements for climate change mitigation as it discusses potential insights for cases of transnational climate adaptation. The analysis is based on analytical theoretical modelling, using a game theoretical model in which countries first choose between joining and not joining an international coalition. Then the coalition members choose their level of emissions cooperatively in a game between the coalition and the outsiders. It includes the possibility of multiple parallel climate clubs, focusing on their potential to enhance cooperation and emissions abatement. Further, the influence of political pressure groups (lobbies) that represent the interests of the industry and environmentalists on the stability of international environmental agreements is examined. This is done by augmenting the basic model of international environmental agreements with a politico-economic model of political contributions. The potential of trade sanctions to induce international cooperation for climate protection is assessed in an analytical model and the effects of these trade measures are then quantified in a static multi-region, multi-sector computable general equilibrium model of globaltrade and energy.

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III, Albert Roy Leatherman. « Brazil as an Emerging Power : Its Role in the Transition to a Multipolar Order and the Consequences for Its Relations with the United States ». Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/101/101131/tde-23072013-105218/.

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This master\'s thesis examines the effects of Brazil\'s economic and political rise on the nation\'s ability to have shaped global order through soft balancing during the presidency of Luiz Inácio Lula da Silva and the consequent impact on Brazil\'s relations with the United States. In order to contextualize the effects of Brazil\'s soft balancing on international institutions and Brazilian-American relations, this text first reviews the relevant theoretical and empirical literature on the liberal peace (and, conversely, trade-based conflicts), the democratic peace, and the nature and evolution of global governance. In the context of both the liberal peace and global governance, the literature implies the potential either for Brazilian-American cooperation to have grown or for heightened conflict to have arisen from the countries\' opposing interests and quests for influence in the transformation to a multipolar world. Meanwhile, the literature posits the potential for shared values to have promoted bilateral harmony but also points to shortcomings in Brazil\'s democratic consolidation that may have undermined the relevance of democracy as a catalyst for Brazilian-American relations during Lula\'s presidency. The empirical analysis in this text, after briefly examining Brazil\'s past quest for power vis-á-vis the United States and Lula\'s limited expansion of Brazil\'s hard (military) power, focuses on Lula\'s use of soft power as a tool to balance American influence in South America and around the world. Lula pursued a classic middle-power soft-balancing strategy by building regional and global coalitions and leveraging international institutions. Although Lula\'s efforts at coalition-building had somewhat limited effects, Brazil\'s soft-balancing strategy nevertheless succeeded in making Brazil\'s positions more consequential to global governance and American policy. Lula\'s incremental progress in checking American influence and solidifying Brazil\'s status as a middle power generally led to friction between Brazil and the United States, although the two countries were able to maintain constructive relations in areas of shared values and interests.
Esta dissertação de mestrado analisa os efeitos da ascensão econômica e política do Brasil sobre a capacidade do país em haver moldado a ordem global via soft balancing durante a presidência de Luiz Inácio Lula da Silva, bem como o consequente impacto dessa ascensão sobre as relações do Brasil com os Estados Unidos. A fim de contextualizar os efeitos do soft balancing brasileiro em instituições internacionais e nas relações brasileiro-americanas, este texto realiza, primeiramente, uma revisão da literatura teórica e empírica pertinente relativa a paz liberal (e, inversamente, conflitos relacionados ao comércio), a paz democrática e a natureza e evolução da governança global. No contexto tanto da paz liberal quanto da governança global, a literatura sugere o potencial ou de aumento da cooperação entre Brasil-Estados Unidos ou de intensificação do conflito decorrente de interesses divergentes dos países e da busca por influência na transformação para um mundo multipolar. Paralelamente, a literatura indica o potencial de que valores compartilhados tenham promovido harmonia bilateral, mas aponta ainda para as limitações da consolidação democrática do Brasil, cujos efeitos podem ter enfraquecido a importância da democracia como um catalisador das relações brasileiro-americanas durante a presidência de Lula. A parte empírica deste texto, após uma breve análise da história de busca brasileira por poder vis-à-vis aos Estados Unidos e da limitada expansão do hard power (poder militar) brasileiro, foca-se no uso que Lula fez do soft power como forma de contra-balancear a influência americana na América do Sul e ao redor do mundo. Lula adotou uma estratégia clássica de soft balancing de potências intermediárias por meio da construção de coalizões regionais e globais, além da influência em instituições internacionais. Apesar dos limitados resultados dos esforços de Lula em formar coalizões, a estratégia brasileira de soft balancing foi, no entanto, bem sucedida em tornar a posição brasileira mais relevante para a governança global e a política americana. Apesar dos dois países terem sido capazes de manter relações construtivas em áreas de interesse e valores comuns, o progresso crescente de Lula em limitar a influência americana e solidificar a posição brasileira de potência intermediária levou, de maneira geral, a atritos entre Brasil e Estados Unidos.

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Thèses sur le sujet « Formation de coalition »

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