{"title":"Fair allocation in hierarchies: A compromise between marginalism and egalitarianism","authors":"Takaaki Abe , David Lowing , Satoshi Nakada","doi":"10.1016/j.jmateco.2025.103128","DOIUrl":"10.1016/j.jmateco.2025.103128","url":null,"abstract":"<div><div>This paper explores the fair allocation of economic surplus among individuals within hierarchical social structures, incorporating the seemingly conflicting principles of marginalism and egalitarianism. We formalize this situation as cooperative games with permission structures and introduce a novel class of allocation rules called <em>egalitarian permission values</em>, extending the traditional egalitarian Shapley values. Our main contribution lies in establishing an axiomatic foundation for this class of rules through a monotonicity axiom. Additionally, we provide a monotonicity-based foundation for the permission value as a special case. Our results also reveal that, in the presence of hierarchical structures, a monotonicity property alone is insufficient to justify the adoption of linear allocation rules, contrasting with the conventional findings in the literature.</div></div>","PeriodicalId":50145,"journal":{"name":"Journal of Mathematical Economics","volume":"119 ","pages":"Article 103128"},"PeriodicalIF":1.0,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144106202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Overreacting to a black box","authors":"Shohei Yanagita","doi":"10.1016/j.jmateco.2025.103131","DOIUrl":"10.1016/j.jmateco.2025.103131","url":null,"abstract":"<div><div>We often receive recommendations whose generation process is so complex that we cannot understand it. In such cases, we cannot perform accurate Bayesian updating. Moreover, it is well-documented that when such recommendations are unexpected for us, we often overreact to them. Based on the framework established by Ke, Wu, and Zhao (2024), we characterize an updating rule expressing such a reaction. In the resulting updating rule, if the distance between the recommendation and the decision maker’s prior belief is significant enough, she perceives it as unexpected and overreacts. This rule can be seen as a generalization of the contraction rule, proposed by Ke, Wu, and Zhao (2024).</div></div>","PeriodicalId":50145,"journal":{"name":"Journal of Mathematical Economics","volume":"118 ","pages":"Article 103131"},"PeriodicalIF":1.0,"publicationDate":"2025-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143937669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Resolute and symmetric mechanisms for two-sided matching problems","authors":"Daniela Bubboloni , Michele Gori , Claudia Meo","doi":"10.1016/j.jmateco.2025.103130","DOIUrl":"10.1016/j.jmateco.2025.103130","url":null,"abstract":"<div><div>We focus on the one-to-one two-sided matching model with two disjoint sets of agents of equal size, where each agent in a set has preferences on the agents in the other set modeled by a linear order. A matching mechanism associates a set of matchings to each preference profile; resoluteness, that is the capability to select a unique matching, and stability are important properties for a matching mechanism. The two versions of the deferred acceptance algorithm are resolute and stable matching mechanisms but they are unfair since they strongly favor one side of the market. We introduce a property for matching mechanisms that relates to fairness; such property, called symmetry, captures different levels of fairness and generalizes existing notions. We provide several possibility and impossibility results mainly involving the most general notion of symmetry, known as gender fairness, resoluteness, stability, weak Pareto optimality and minimal optimality. In particular, we prove that: resolute, gender fair matching mechanisms exist if and only if each side of the market consists of an odd number of agents; there exists no resolute, gender fair, minimally optimal matching mechanism. Those results are obtained by employing algebraic methods based on group theory, an approach not yet explored in matching theory.</div></div>","PeriodicalId":50145,"journal":{"name":"Journal of Mathematical Economics","volume":"118 ","pages":"Article 103130"},"PeriodicalIF":1.0,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143946815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Robust personal equilibrium effects in misspecified causal models","authors":"Juan Carlos Carbajal , John Nachbar","doi":"10.1016/j.jmateco.2025.103127","DOIUrl":"10.1016/j.jmateco.2025.103127","url":null,"abstract":"<div><div>Following the work of Spiegler (2016), we use directed acyclical graphs (DAGs) to model a decision maker (DM) who is boundedly rational in the sense of having a misspecified causal model. Spiegler (2016) shows that certain misspecifications can lead to <em>personal equilibrium effects</em>: the DM calculates conditional probabilities of the relevant state variables incorrectly, and the DM’s action influences her interpretation of the data in ways that exacerbate this issue. We show that these personal equilibrium effects are <em>robust</em>, i.e., they do not depend on the details of the underlying distribution. We provide an exact characterization of when robust personal equilibrium effects arise, which is formulated in terms of structural conditional independence assertions of the DM’s misspecified DAG. Examples demonstrate how sensitive robust PE effects are to the structural details of the subjective DAG that, in most cases, are the DM’s private information. We consider detecting robust personal equilibrium effects under partial knowledge of the DM’s misspecified causal model.</div></div>","PeriodicalId":50145,"journal":{"name":"Journal of Mathematical Economics","volume":"118 ","pages":"Article 103127"},"PeriodicalIF":1.0,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143941959","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Return expectations across the wealth distribution","authors":"Edouard Djeutem , Shaofeng Xu","doi":"10.1016/j.jmateco.2025.103132","DOIUrl":"10.1016/j.jmateco.2025.103132","url":null,"abstract":"<div><div>This paper examines how a household’s expectation of asset returns varies with wealth. In the model, households face idiosyncratic investment risks and confront Knightian uncertainty about returns on the risky asset. Their return expectations are formed out of a dynamic zero-sum game with nature. We characterize the robust consumption–investment policies using a perturbation method. The model predicts a U-shaped relationship between expected risky returns and wealth, as nature is less incentivized to distort the perceptions of both poor and rich households. We confront this prediction with U.S. survey data.</div></div>","PeriodicalId":50145,"journal":{"name":"Journal of Mathematical Economics","volume":"118 ","pages":"Article 103132"},"PeriodicalIF":1.0,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143937668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Haris Aziz , Alexander Lam , Barton E. Lee , Toby Walsh
{"title":"Proportionality-based fairness and strategyproofness in the facility location problem","authors":"Haris Aziz , Alexander Lam , Barton E. Lee , Toby Walsh","doi":"10.1016/j.jmateco.2025.103129","DOIUrl":"10.1016/j.jmateco.2025.103129","url":null,"abstract":"<div><div>We focus on a simple, one-dimensional collective decision problem (often referred to as the facility location problem) and explore issues of strategyproofness and proportionality-based fairness. Our focus is on the Unanimous Fair Share (UFS) axiom—a strengthening of the proportionality axiom (as in Freeman et al., 2021) We characterize the family of strategyproof and UFS mechanisms and also strategyproof and proportional mechanisms. We show that imposing strategyproofness renders the combination of proportionality and unanimity to be equivalent to UFS. Furthermore, there is a unique mechanism that satisfies strategyproofness and UFS (or, equivalently, proportionality and unanimity): the Uniform Phantom mechanism, which is studied in Freeman et al. (2021). This result strengthens known characterizations in the literature. We also provide an alternative characterization of the outcomes of the Uniform Phantom mechanism as the unique (pure) Nash equilibrium outcome for any mechanism that satisfies continuity, strict monotonicity, and UFS. Finally, we analyze the approximation guarantees, in terms of optimal social welfare, obtained by mechanisms that are strategyproof and satisfy the UFS (and proportionality) axiom. We show that the Uniform Phantom mechanism provides the best approximation of the optimal social welfare among all mechanisms that satisfy UFS (or proportionality).</div></div>","PeriodicalId":50145,"journal":{"name":"Journal of Mathematical Economics","volume":"119 ","pages":"Article 103129"},"PeriodicalIF":1.0,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144106201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Bargaining-Equilibrium equivalence","authors":"Anuj Bhowmik , Sandipan Saha","doi":"10.1016/j.jmateco.2025.103117","DOIUrl":"10.1016/j.jmateco.2025.103117","url":null,"abstract":"<div><div>The paper tries to answer one of the more nascent questions in the literature on general equilibrium theory by investigating the equivalence between the set of club equilibrium allocations and the bargaining set for a club economy. Clubs in this framework are treated in a parallel fashion to private goods as articles of choice. Each club comprises two components: (i) the profile of the club and (ii) the club project. We define a two-step veto mechanism and introduce the bargaining set in line with Aumann et al. (1961) for such an economy. In this paper, we establish that non-club-equilibrium allocations are those against which there exists a set of agents and a price vector at which they agree to trade amongst themselves rather than consume the non-club-equilibrium allocation assigned to them and all other agents (weakly) prefer the non-club-equilibrium allocation to trading at that particular price vector. In other words, there is a Walrasian objection to any non-club equilibrium allocation. We further show that Walrasian objections are also justified, which helps us to establish our equivalence between the set of equilibrium allocations and the bargaining set for an atomless club economy.</div></div>","PeriodicalId":50145,"journal":{"name":"Journal of Mathematical Economics","volume":"118 ","pages":"Article 103117"},"PeriodicalIF":1.0,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143870709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Group dominant networks and convexity","authors":"Christophe Bravard , Sudipta Sarangi , Hector Tzavellas","doi":"10.1016/j.jmateco.2025.103116","DOIUrl":"10.1016/j.jmateco.2025.103116","url":null,"abstract":"<div><div>We study group dominant networks under convexity alone and in combination with either strategic complementarity or substitutability. Group dominant networks consists of one group of completely connected agents and a set of isolated agents. They arise frequently in the networks’ literature, most commonly in collaborative situations. We first provide two conditions that help us select from different equilibrium group dominant networks. They allow us to provide a characterization of equilibrium networks for both strategic complementarity and substitutability cases including identifying conditions for uniqueness. Next we observe that under strategic substitutability the equilibrium set may not be a convex interval, allowing for the possibility of ‘holes’ in it. We provide conditions to eliminate these holes and show that this approach can also help to simplify the process of identifying group dominant equilibria.</div></div>","PeriodicalId":50145,"journal":{"name":"Journal of Mathematical Economics","volume":"118 ","pages":"Article 103116"},"PeriodicalIF":1.0,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143738744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"An economic theory of the Soviet system","authors":"Maxime Menuet , Antoine Parent","doi":"10.1016/j.jmateco.2025.103115","DOIUrl":"10.1016/j.jmateco.2025.103115","url":null,"abstract":"<div><div>The sudden collapse of the Soviet regime is one of the most enigmatic historical events explored in the social sciences. In this paper, we propose a macrodynamic theory of the Soviet economy that provides theoretical foundations for understanding its collapse. Our model features three actors: workers (the people) who can revolt, natchalnik (the supervisor of firms) who controls a defense-industry firm, and the apparatchik (a member of the communist party and administration) who both extracts production for personal uses and acts as a central planner. We analyze the conditions for the Soviet regime’s sustainability or collapse. Our theory identifies three channels leading to the collapse: internal contradictions within the elite, conflicts between the workforce and the administrative-command structure, and corruption among the elite.</div></div>","PeriodicalId":50145,"journal":{"name":"Journal of Mathematical Economics","volume":"118 ","pages":"Article 103115"},"PeriodicalIF":1.0,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143738745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Pricing negative externalities in social networks","authors":"Guopeng Li , Sijie Wang , Yifan Xiong , Feng Zhu","doi":"10.1016/j.jmateco.2025.103105","DOIUrl":"10.1016/j.jmateco.2025.103105","url":null,"abstract":"<div><div>We explore optimal monopoly pricing in the presence of local negative externalities among agents’ consumption. A monopolist first sets personalized prices, and consumers then simultaneously determine consumption levels. When network externalities are relatively small, the complement graph of the social network plays a key role in characterizing the equilibrium. Optimal prices are uniform when the production cost is linear and proportional to agents’ Katz-Bonacich centralities in the complement network when the production cost is convex. We further connect agents’ consumption with their degrees in several typical networks. The firm’s profit and total consumption decrease with network density, although the consumption of a specific agent may not decrease accordingly. Furthermore, in the context of directed networks, the monopolist charges higher prices to agents who generate substantial externalities for others without being reciprocally influenced. We also apply our model to the case involving large network externalities, where the monopolist exclusively sells products to consumers who constitute a maximum independent set.</div></div>","PeriodicalId":50145,"journal":{"name":"Journal of Mathematical Economics","volume":"118 ","pages":"Article 103105"},"PeriodicalIF":1.0,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143683355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}