Stable Coalition Research Articles

Competitive and Cooperative Assortment Games under Markov Chain Choice Model

In this work, we study the assortment planning games in which multiple retailers interact in the market. Each retailer owns some of the products and their goal is to select a subset of products, that is, an assortment to offer to the customers so as to maximize their expected revenue. The purchase behavior of the customer is assumed to follow the Markov chain choice model. We consider two types of assortment games under the Markov chain choice model—a competitive game and a cooperative game. In the assortment competition game, we show that there always exists a pure‐strategy Nash equilibrium and such equilibrium can be found in polynomial time. We also identify an easy‐to‐check condition for the uniqueness of the Nash equilibrium. Then we analyze the equilibrium outcome of this competition game, and compare the outcome with that in a monopolistic setting and a central planner setting. We show that under the assortment competition game, each retailer will offer a broader assortment in the equilibrium, which could include products that are not profitable in the monopolistic or the central planner setting, and it will eventually lead to a decrease in revenue for each player. Furthermore, we show that the price‐of‐anarchy and the price‐of‐stability of the game can be arbitrarily large. Motivated by these results, we further consider the assortment cooperation game under the Markov chain choice model, in which retailers are allowed to form coalitions. We consider two settings of cooperative games distinguished by the way we assume other players’ behaviors outside a coalition. Interestingly, we find that when the players are assumed to be intrinsically competitive (meaning that players outside a coalition are assumed to be a collection of competing players), then there is incentive for all the players to form a grand coalition and there exists an allocation of the total revenue that makes the coalition stable (exists a core to the game). However, when the players are assumed to be intrinsically collaborative (meaning that players outside a coalition are assumed to form another coalition), then a stable coalition may not exist.

Advocacy coalitions, beliefs, and learning: An analysis of stability, change, and reinforcement

AbstractPolicy processes are ongoing phenomena without beginning or end. Accordingly, a major focus of research has been on questions of stability and change. This paper continues in this tradition by examining advocacy coalition stability, belief change, and learning. This paper draws on three waves of policy actor surveys that compare panel and non‐panel samples. The data were collected in 2013, 2015, and 2017 in the context of oil and gas development in Colorado, USA. The findings mostly confirm that coalitions and beliefs tend to be stable and that learning leans toward reinforcement rather than change in beliefs. However, although rare, some instances of belief change, change in coalition membership, and changing policy positions occur. This paper makes theoretical and empirical contributions to the study of stability, change, and reinforcement of advocacy coalitions and their beliefs and charges policy scholars to look more at the exceptions to the evidence rather than the confirmations.

Agglomeration bonus and endogenous group formation

AbstractAgglomeration bonus schemes are envisioned to incentivize the connectivity of habitat conservation across landowners. Assuming full cooperation among landowners at the landscape scale, the bulk of the literature theoretically finds that agglomeration bonus schemes are more cost effective in achieving biodiversity conservation than spatially homogenous payments. However, it may be rational for landowners not to cooperate all together but, rather, to cooperate within smaller groups. Here, we analyze the cost effectiveness of agglomeration bonus schemes when such partial cooperation is allowed, that is, when cooperation is endogenously chosen. We introduce a spatially explicit ecological‐economic model within a coalition formation game to assess how landowners form stable coalition structures and how this affects biodiversity conservation under a wide range of (i) degrees of spatial cost autocorrelation, (ii) bonuses and flat‐rate payments, (iii) species dispersal rates, and (iv) coordination costs. We find that agglomeration bonus schemes are more cost effective than homogenous payments only for low public expenditures. This condition is not identified if full cooperation is assumed. We find, however, that full cooperation never emerges and hence that such an assumption leads to an overestimation of the cost effectiveness of agglomeration bonus schemes. Moreover, we find that the cost effectiveness of agglomeration bonus schemes increases when the spatial cost autocorrelation and species dispersal rate decrease. Finally, coordination costs do not affect the cost effectiveness of the agglomeration bonus scheme but they have implications for its design because of their impact on coalition formation.

Stable coalition structures and power indices for majority voting

AbstractAn (n,k)‐game is a voting game in which each player has exactly one vote, and decisions are made by at least k affirmative votes of the n players. A power index shows the a priori power of the n voters. The purpose of this paper is to show what axioms of power indices generate stable coalition structures for each (n,k)‐game. Using the stability notion of the core, we show that a coalition structure containing a minimal winning coalition is stable for a wide range of general power indices satisfying a set of axioms, such as the Shapley–Shubik, Banzhaf, normalized Banzhaf, and Deegan–Packel power indices. Moreover, we also show that a coalition structure that represents a two‐party system can be stable if the two large parties are close enough in size. Some unstable coalition structures are also analyzed.

Structural Stability of Coalitions: A Formal Model Highlighting the Role of Participants Positioned between Members and Neutral Actors

Given a fixed network that links various actors, we introduce a formal model that describes the structural stability of coalitions. To this end, we used the partition of the set of all actors in three distinct positions: members, i.e., those who are central to a coalition; participants, i.e., those who are not actively engaged with the issues at hand; neutral actors, i.e., non-members, those who are not party to any interests and outside the coalition. Using the language of networks, we formulated three assumptions that may be used to characterize the stability of this partition. We paid particular attention to the role of participants as they facilitate or complicate extensions of a given coalition. Given the fixed network, we (1) illustrate the verification of the stability of a coalition, (2) provide existence results of stable coalitions, and (3) set the limits to their credible extensions. Our three formal assumptions may serve as a platform for discussions regarding the stability of coalitions.

Towards an ever stronger politicization? How members of the European Parliament deal with values in social networks

ABSTRACT Since the 2000s, the reference to ‘values’ has become a key topic in the legitimation and politicization of the European Union (EU). This article studies to which extent and how members of the European Parliament (MEPs) mobilize values in their Facebook communication and whether it contributes to the politicization – understood as polarization – of their discourse. Our findings show that references to values are minor in MEPs’ Facebook discourse. Differences are visible along national and party lines and according to issues at stake. However, no clear patterns emerge to relate specific value narratives to stable coalition- or conflict-lines. Empirically, the article analyses Facebook posts by MEPs of four nationalities (France, Italy, Poland and Hungary) in pre- and post-electoral times (March 2019 – March 2020). Theoretically, it contributes to the literature on the politicization and legitimation of the EU ; and on MEPs’ communication and use of social networks.

A Stable Payoff Allocation Protocol for Controlling the Selfishness and Managing the Power Consumption in Mobile Ad Hoc Networks

We present a model to control the mobile nodes’ selfish behavior in Mobile Ad Hoc Networks using the cooperative game. We design the model such that a path from a source node to a destination node is a stable coalition among the nodes. We achieve this by compensating the nodes using virtual currency to take part in the coalition formation. The incentive provided to a node taking part in the coalition is determined using the Shapley value of the coalition formed. We also design the model to use minimum power to reach the one-hop node in the communication path. We achieve each node’s dynamic power control while forming the coalition among the nodes in the path from the source node to the destination node. In addition to these, we design the model where a node in the path should be truthful regarding the power requiring to reach a one-hop node. Finally, we perform a rigorous simulation to check the performance of the model.

ОБ ОДНОЙ МОДИФИКАЦИИ РАВНОВЕСИЯ ПО НЭШУ

By the end of the last century there were four areas in the mathematical theory of positional differential games: non-coalitional positional differential games, cooperative, hierarchical and, finally, the least-understood coalitional positional differential games. In their turn, coalitional games are divided into games with transferable payoffs (games with side payments when players can split profits in the course of the game) and with non-transferable payoffs (games with side payments when there are no such distributions for this or that reason). The coalitional games with side payments are being extensively explored at the Faculties of Applied Mathematics and Management Processes of St. Petersburg University and the Institute of Mathematics and Information Technologies of Petrozavodsk State University (by Professors L.A. Petrosyan, V.V. Mozalov, E.M. Parilina, A.N. Rettieva and their numerous students). However, side payments are not always present even in economic cooperation; moreover, side payments can be legislated against. We believe that the research of the equilibrium of threats and counter-threats (sanctions and counter-sanctions) in non-coalitional differential games that we have carried out over the last years allows to also cover some aspects of non-transferable payoff coalitional games. The article considers the issues of namely the internal and external stability of coalitions in the class of positional differential games. The coefficient constraints were identified for the mathematical model of a linear-quadratic differential positional game with twin-coalitional structure for six persons where this coalitional structure is internally and externally stable.

Israeli Parlamentarism in XXI Century: Electorial Failure or System Crises?

Just within three years Israel experienced four consecutive Knesset electoral campaigns (in April and September 2019; March 2020 and March 2021). However, neither leader of the permanently ruling since 2009 center-right Likud party Benjamin Netanyahu, no his electoral opponents were able to form in any way stable coalition Government. In fact the electoral campaign during this period due to the uncompromised rivalry between the major party blocs never terminated. In March 2021, at last, the anti-Netanyahu bloc managed to win electionsand form the coalition government. Such situation that hardly had any precedent in Israeli political history, as well as the obvious deadlock that Israeli political system appeared poses several questions that yet to find their comprehensive answer in the academic literature. Do we deal with a situational political "glitch", which - exactly as it had happened in the past, could be resolved at some point? Or, on the contrary, do we observe here the systematic crises of the party and political system of this country, which basic foundations were constructed long before the declaration of the State of Israel itself? Finally, considering similar political trends in other Western countries, could we talk about the general crises of the European-style parliamentary democracy model, the one that during the past centuries was believed to be the optimal political structure framework for modern and contemporary ethnic national and civic national states? While analyzing the Israeli experience the authors of this article intend to answer a part of these and related questions.

Stable Coalition Structures: Characterizations and Applications of Hart and Kurz’s Four Stability Concepts

Stable Coalition Structures: Characterizations and Applications of Hart and Kurz’s Four Stability Concepts

Existence of Stable Coalition Structures in Three-player Games with Graph-constrained Solution

The stability of coalition structures is investigated in the sense that no player prefers to individually deviate from the current coalition considering his utility. This principle is close to the concept of the Nash equilibrium. The evaluation of each player's utility is determined with respect to the solution concept- the Shapley value with exogenous directed graph constraint. The existence of a stable coalition structure with respect to such a solution is examined for two-player as well as three-player games.

Multi-plant direct heat integration considering coalition stability under unplanned shutdown risks

Multi-plant heat integration can increase total profits of industrial parks. The relationship among different plants can be regarded as a cooperative coalition. Current researches are mainly focused on recovering waste heat through many inter-plant heat exchangers while ignoring the stability of the multi-plant coalition. When unplanned shutdown occurs, corresponding plants may be unsatisfied with their profits due to those invalid inter-plant exchangers and prefer not to join this multi-plant cooperation. Therefore, there should be a tradeoff between inter-plant heat duties and the stability of the multi-plant cooperation. In this study, Owen-based core constraints are incorporated into a multi-plant direct HEN model to deal with cost savings and coalition stability simultaneously. Two cases compare the financial effectiveness and the profit allocation of our designs with other researches. Results show that the total costs have been reduced and each plant can receive acceptable profits from this multi-plant heat integration under shutdown risks between 0% and 100%.

Damage sensitivity and stability in international environmental agreements

Abstract This article examines the formation of International Environmental Agreements (IEAs). The economic literature focuses on scenarios where countries are weakly sensitive to environmental damages (constant or linear marginal damages) and finds that stable coalitions are small when countries choose their emission strategies simultaneously and the marginal benefit function is linear. Motivated by empirical evidence, our analysis addresses cases where countries are highly sensitive to environmental damages. In this context, we find equilibrium behaviors that reverse conventional wisdom. For instance, large coalitions including the grand coalition can be supported as an equilibrium outcome when the sensitivity of countries to environmental conditions its high. Our findings provide an additional explanation for large-scale IEAs such as the Montreal Protocol.

Pre-electoral coalitions and cabinet stability in presidential systems

Previous research on coalition stability in presidential systems has relied to a substantial extent on the parliamentary literature. By focusing on the post-electoral bargaining environment, these approaches have neglected the key role played by pre-electoral agreements formed around the winning presidential candidate in the making and breaking of coalitions under presidentialism. We claim that cabinets derived from pre-electoral coalition should foster trust and reduce uncertainty regarding partners’ future behaviour. However, the positive effect of pre-electoral coalitions over cabinet duration is conditional on cabinet status, that is, the control of a legislative majority or near majority. Therefore, we argue that pre-electoral coalition cabinets holding a majority or near majority of seats will be more durable than purely post-electoral majority coalitions, whereas minority pre-electoral coalition cabinets congruent should endure less than minority post-electoral coalition cabinets. We test these hypotheses using a dataset of pre- and post-electoral coalitions in 11 Latin American countries.

Cost-Optimized Microgrid Coalitions Using Bayesian Reinforcement Learning

Microgrids are empowered by the advances in renewable energy generation, which enable the microgrids to generate the required energy for supplying their loads and trade the surplus energy to other microgrids or the macrogrid. Microgrids need to optimize the scheduling of their demands and energy levels while trading their surplus with others to minimize the overall cost. This can be affected by various factors such as variations in demand, energy generation, and competition among microgrids due to their dynamic nature. Thus, reaching optimal scheduling is challenging due to the uncertainty caused by the generation/consumption of renewable energy and the complexity of interconnected microgrids and their interplay. Previous works mainly rely on modeling-based approaches and the availability of precise information on microgrid dynamics. This paper addresses the energy trading problem among microgrids by minimizing the cost while uncertainty exists in microgrid generation and demand. To this end, a Bayesian coalitional reinforcement learning-based model is introduced to minimize the energy trading cost among microgrids by forming stable coalitions. The results show that the proposed model can minimize the cost up to 23% with respect to the coalitional game theory model.

Cost Allocation for Less-Than-Truckload Collaboration via Shipper Consortium

We study the problem of collaborative less-than-truckload (LTL) transportation in the form of a shipper consortium, which is operated by a third-party logistics provider (3PL) through a cross-dock/pooling network. The 3PL has responsibility for planning the combined loads prior to actual shipments, hiring and routing carriers to execute shipping, and allocating the cost to the shippers in the consortium. Shippers receive substantial cost savings from combined truckload shipments. However, achieving consolidation and realizing this benefit requires addressing two essential issues: (i) how to find an approximately optimal consolidation solution in a large network with many freights and (ii) how to determine a fair cost allocation rule among the shippers’ consolidated freights that ensures budget balance while minimally violating coalitional stability. Our work resolves these two issues. We formulate a time-space network flow model of the problem under both incremental and all-unit discount structures of LTL rates and propose a computationally efficient algorithm based on local search heuristics. We model the problem of allocating cost to the shippers as a cooperative game. We decompose and linearize the Lagrangian dual problem by using total unimodularity and concavity. We propose an efficiently computable cost allocation rule from the linearized dual models. The dual rule ensures stable cooperation but may have underallocation equal to a duality gap. To cover the underallocation, we further develop a budget covering procedure and define an [Formula: see text]-core allocation with desirable properties. Through extensive computational experiments, we find that the shipper consortium reduces total shipping costs by more than 40% in most cases; meanwhile, the [Formula: see text]-core allocation is typically in the core for small-scale networks while violating stability by at most 5% for large-scale networks and provides consolidated freights with more than 50% individual cost savings on average.

DEVELOPMENT OF LOW-CARBON POWER TECHNOLOGIES AND THE STABILITY OF INTERNATIONAL CLIMATE COOPERATION

This paper explores the effects of the technological development of key low-carbon power technologies (photovoltaic (PV), wind, and carbon capture and storage (CCS)) on the stability of global climate cooperation under several assumptions about climate-related damage. The methodology combines cooperative game theory with a global computable general equilibrium (CGE) model allowing us to endogenize testing of stability of the global coalition and to include macroeconomic effects. Global cooperation is found to be stable only under mean or pessimistic assumptions about the development of key low-carbon power technologies and when damage is severe. If the technological development is favorable or climate damage is not severe, the gains from global cooperation are not sufficient to compensate for mitigation costs, because a nonglobal coalition of willing countries can then achieve emission reductions close to the global optimum. Finally, our findings support establishing nonglobal ‘climate clubs’ to overcome the lack of global cooperation in international climate policy.

Environmental agreements, research and technological spillovers

This paper considers different contracts of international environmental agreements in a dynamic game in which countries choose emissions, R&D investments and investments in renewable energy generation capacity. R&D investments cause technological spillovers. For the different contracts the size of the stable coalition is analyzed. It turns out that both cooperation over R&D investments and technology transfers within the coalition may enhance the size of stable coalitions. In an empirical calibration, the stable coalition of the complete contract is quite small. An incomplete contract over emission leads to larger stable coalitions which can be further enlarged by a technology transfer within the coalition. An incomplete contract over emissions and R&D investments is the best performer and yields the largest stable coalition up to the grand coalition. The incomplete contract over emissions and R&D investments is pareto-superior to all other contracts and may even be first best.

Synthesis of stable coalitions in the economy based on fundamental criteria of the portfolio theory

Subject. The article outlines basic principles of a mathematical model for formation of stable coalitions in the economy at the interstate level. Objectives. We focus on developing a mathematical model to build such coalitions. Methods. The study employs the portfolio theory, risk-return model, correlation and regression analysis, technical and fundamental analysis. The proposed model rests on fundamental provisions of creating a multicomponent, widely diversified investment portfolio. The model uses the key concepts, like expected profitability, risk level, industry diversification and hedging, in combination with the synthesis of a diversified group of leading commodity indices. Results. We show possibilities of using internal (based on the country’s indices) and external (based on other countries’ indices) correlation analysis, according to data on trends in economic indices, to ensure sectoral diversification within the country and maximize the international level of sectoral diversification, respectively. We performed a fundamental analysis of the condition of economies of the countries included in the coalition, and of the countries, which are considered to be included in the coalition as appropriate. The paper assesses positive and negative factors of joint functioning of the economies of the coalition countries, from the point of view of their geographic location. Conclusions. The model makes it possible to build new optimal coalitions in the economy, to analyze the practicability of further existence of previously formed coalitions, and to update the composition of coalitions, according to trends in the world economy development.

A strategy-based coalition formation model for hybrid wind/PV/FC/MT/DG/battery multi-microgrid systems considering demand response programs

In this paper, we propose an analytic approach to identify the best coalition among microgrids in multi-microgrid systems. The proposed model evaluates all of the strategies and ranks them from the viewpoint of MGs. At first, the utility of the strategies for each microgrid is calculated. The class of the strategies is determined by their utility, and the best strategy is selected using the average class. The proposed algorithm enjoys a cooperative game and provides a stable coalition for microgrids. In this cooperative game, the overall gain of each strategy is divided among the cooperator microgrids based on their contributions. We utilize the Shapley value to allocate the cost of each cooperator microgrid in a strategy. The Shapley value assigns a unique distribution function for each actor to determine a fair allocation. The proposed scheme is applied to the standard small-scale and large-scale systems. The results of case studies demonstrate that the proposed coalition formation significantly reduces the operating cost of the system and the amount of involuntary load shedding. Also, the proposed model improves the total operating costs of the small-scale and large-scale multi-microgrid systems by 19.98 and 19.44 percent, respectively.