{"title":"Choquet expected utility and never best choice","authors":"Christopher Kops, Hans Peters, Dries Vermeulen","doi":"10.1016/j.jmateco.2025.103188","DOIUrl":"10.1016/j.jmateco.2025.103188","url":null,"abstract":"<div><div>Given a set of capacities describing uncertainty over a set of states, and a set of acts, the question is considered when an act is never a best choice, i.e., when for every capacity there is another act with higher Choquet expected utility. This question is answered for several sets of capacities, distinguished by their supports, where the focus is on four different definitions of a support. One consequence of the analysis is that an act is never a best choice against the set of all capacities if and only if it is strictly dominated by a convex combination of the comonotonized versions of the other acts. This result can be seen as the counterpart of the analogous result for additive capacities, such as mixed strategies in games.</div></div>","PeriodicalId":50145,"journal":{"name":"Journal of Mathematical Economics","volume":"121 ","pages":"Article 103188"},"PeriodicalIF":0.7,"publicationDate":"2025-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145362886","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":"Hotelling competition with discrete consumers","authors":"Martin C. Byford","doi":"10.1016/j.jmateco.2025.103189","DOIUrl":"10.1016/j.jmateco.2025.103189","url":null,"abstract":"<div><div>Populating the Hotelling line with finitely many consumers produces a model of spatial competition that is challenging to analyse as it does not possess a Nash equilibrium in pure strategies. This paper characterises the mixed-strategy Nash equilibrium (MSNE) for the model. The MSNE is unique, symmetric, and its support converges to the equilibrium of the standard Hotelling model — with a continuum of consumers — from above. The results suggest that the standard model is a reasonable approximation of the MSNE for a market with a large number of discrete buyers. By contrast, the intensity of competition is significantly lower when the market is home to a small numbers of buyers. In this case the MSNE expected prices and profits are well above the equilibrium prices and profits of the standard model.</div></div>","PeriodicalId":50145,"journal":{"name":"Journal of Mathematical Economics","volume":"121 ","pages":"Article 103189"},"PeriodicalIF":0.7,"publicationDate":"2025-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145325115","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":"The tontine puzzle","authors":"An Chen , Alfred Müller , Manuel Rach","doi":"10.1016/j.jmateco.2025.103185","DOIUrl":"10.1016/j.jmateco.2025.103185","url":null,"abstract":"<div><div>Retirement income tontines pool idiosyncratic and systematic longevity risk among their participants. This paper studies conditions under which the cash flow distribution of a tontine dominates that of a traditional life annuity. Building on the almost first order stochastic dominance (AFSD) criterion of Leshno and Levy (2002), we show that properly designed tontines dominate equally priced constant annuities whenever the latter embed actuarial loadings and/or the retiree underestimates the survival probabilities assumed in annuity pricing. In large pools the AFSD relation converges to classical first order dominance. Hence for any preference that is increasing and continuous in consumption, including but not limited to generalized expected utility (GEU) and cumulative prospect theory (CPT) frameworks, retirees prefer a tontine once the pool reaches a modest size. We quantify the minimum number of participants required for dominance under both normative (GEU) and descriptive (CPT) benchmarks and find that one or two digits are typically sufficient. These findings constitute what we label the tontine puzzle: despite their theoretical appeal to retirees, real world tontine markets remain nascent.<span><span><sup>1</sup></span></span></div></div>","PeriodicalId":50145,"journal":{"name":"Journal of Mathematical Economics","volume":"121 ","pages":"Article 103185"},"PeriodicalIF":0.7,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145268046","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":"Design tools for all-pay contests: Aligning incentives and balancing the playing field","authors":"Rui Gao , Jingfeng Lu , Zhewei Wang , Lixue Zhou","doi":"10.1016/j.jmateco.2025.103186","DOIUrl":"10.1016/j.jmateco.2025.103186","url":null,"abstract":"<div><div>In contests where players compete across multiple dimensions, we compare two main design tools available to a designer with a fixed prize budget: <em>prize allocation</em>, which distributes the budget across independent single-dimensional contests, and the <em>scoring rule</em>, which awards the entire budget to the winner based on weighted overall performance. In an all-pay framework with a multiplicative (designer) payoff, the scoring rule dominates prize allocation through two channels: an <em>incentive-alignment effect</em>, aligning players’ strategies with the designer’s objective, and a <em>balancing effect</em>, which favors the weaker player and raises output. When <em>handicaps</em> are introduced as an additional tool, both players’ equilibrium payoffs are zero, eliminating the balancing effect so that only incentive alignment matters. Finally, with additive (designer) payoffs, outputs are substitutes: the scoring rule continues to outperform under asymmetry but coincides with prize allocation under symmetry.</div></div>","PeriodicalId":50145,"journal":{"name":"Journal of Mathematical Economics","volume":"121 ","pages":"Article 103186"},"PeriodicalIF":0.7,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145267995","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":"Impossibility results in the probabilistic assignment problem with stochastic same-sidedness and minimal invariance","authors":"Kiyong Yun","doi":"10.1016/j.jmateco.2025.103183","DOIUrl":"10.1016/j.jmateco.2025.103183","url":null,"abstract":"<div><div>Bogomolnaia and Moulin (2001) demonstrate the impossibility of designing a rule that simultaneously satisfies <em>stochastic dominance efficiency</em>, <em>equal treatment of equals</em>, and <em>stochastic dominance strategy-proofness</em> in the context of the probabilistic assignment problem with indivisible objects. Despite attempts to relax these conditions by introducing concepts like <em>upper contour strategy-proofness</em> or <em>robust ex-post efficiency</em>, the impossibility results remain. Recently, Bandhu et al. (2024) introduced the concept of <em>stochastic same-sidedness</em> in the random voting model. This condition stipulates that if an agent modifies their preference by swapping two consecutively ranked objects, then (1) the sum of probabilities assigned to objects strictly higher than the swapped pair should remain unchanged, and (2) the sum of probabilities assigned to the swapped pair should also remain constant. We first show that the impossibility persists even when <em>stochastic dominance strategy-proofness</em> is weakened to <em>stochastic same-sidedness</em>. We then decompose <em>stochastic same-sidedness</em> into three minimal invariance axioms and use these to establish further impossibility results.</div></div>","PeriodicalId":50145,"journal":{"name":"Journal of Mathematical Economics","volume":"121 ","pages":"Article 103183"},"PeriodicalIF":0.7,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145221459","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":"Preference for mixture and local ambiguity reduction in nonconvex preferences","authors":"Youngsoo Heo","doi":"10.1016/j.jmateco.2025.103182","DOIUrl":"10.1016/j.jmateco.2025.103182","url":null,"abstract":"<div><div>Ambiguity aversion is often modeled as a preference for mixing different alternatives, but such behavior may not be global, emerging only when the mixture sufficiently reduces ambiguity. This paper provides a utility function characterization that accommodates various patterns of mixture preferences by introducing a novel concept called the <em>core bound</em>. A preference for a specific mixture is characterized by the nonemptiness of the core bound, which indicates substantial overall ambiguity but relatively limited ambiguity for that mixture. Several notable special cases of the main theorem include nonconvex preferences as well as the Maxmin Expected Utility preference. Additionally, core bounds are useful in identifying relative ambiguity aversion between two different preference relations.</div></div>","PeriodicalId":50145,"journal":{"name":"Journal of Mathematical Economics","volume":"121 ","pages":"Article 103182"},"PeriodicalIF":0.7,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159265","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":"Prudence and higher-order risk attitudes in the rank-dependent utility model","authors":"Ruodu Wang, Qinyu Wu","doi":"10.1016/j.jmateco.2025.103181","DOIUrl":"10.1016/j.jmateco.2025.103181","url":null,"abstract":"<div><div>We obtain a full characterization of consistency with respect to higher-order stochastic dominance within the rank-dependent utility model. Different from the results in the literature, we do not assume any condition on the utility functions and the probability weighting functions, such as differentiability or continuity. It turns out that the level of generality that we offer leads to models that do not have a continuous probability weighting function and yet they satisfy prudence. In particular, the corresponding probability weighting function can only have a jump at 1, and must be linear on <span><math><mrow><mo>[</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>)</mo></mrow></math></span>.</div></div>","PeriodicalId":50145,"journal":{"name":"Journal of Mathematical Economics","volume":"121 ","pages":"Article 103181"},"PeriodicalIF":0.7,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159264","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":"Obvious representations","authors":"Lorenz Hartmann , Jean Baccelli","doi":"10.1016/j.jmateco.2025.103172","DOIUrl":"10.1016/j.jmateco.2025.103172","url":null,"abstract":"<div><div>Under standard assumptions, the respect of obvious dominance characterizes the existence of what we call <em>obvious representations</em>. We show that various conditions imposed directly on these representations pin down general monotonic, invariant bi-separable, general Choquet, convex Choquet, neo-additive Choquet, and subjective expected utility preferences. Among other insights, the alternative axiomatizations which we thus provide facilitate comparisons between models, as well as the identification of their parameters. Co-minimal and co-maximal acts — a natural generalization of co-monotonic acts, the relevance of which is further confirmed by our results — play a significant role in our analysis. Our results further testify of the fundamental importance of obvious dominance, and they offer a proof of concept that obvious representations constitute a fruitful format for axiomatic investigations.</div></div>","PeriodicalId":50145,"journal":{"name":"Journal of Mathematical Economics","volume":"121 ","pages":"Article 103172"},"PeriodicalIF":0.7,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097423","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":"Ekici’s reclaim-proof allocations revisited","authors":"Qianfeng Tang , Zhan Zhu","doi":"10.1016/j.jmateco.2025.103170","DOIUrl":"10.1016/j.jmateco.2025.103170","url":null,"abstract":"<div><div>We revisit the concept of reclaim-proof allocations proposed by <span><span>Ekici (2013)</span></span> for house allocation problems with existing tenants. As a concept of core, the definition of reclaim-proof allocations assumes that when a coalition blocks an allocation, an agent in the coalition is allowed to bring her allocated object into the coalition, even when it is privately owned by an outsider. We propose a new notion of core called the effectual core by restoring the feasibility of coalitional blocking in Ekici’s definition. Our main result shows that the effectual core, while by definition weaker than reclaim-proofness, is actually equivalent to it. Together with Ekici’s results, it is then immediate that an allocation is in the effectual core if and only if it is produced by the <em>You request my house-I get your turn</em> (YRMH-IGYT) mechanism (<span><span>Abdulkadiroğlu and Sönmez, 1999</span></span>) and if and only if it is a competitive allocation.</div></div>","PeriodicalId":50145,"journal":{"name":"Journal of Mathematical Economics","volume":"121 ","pages":"Article 103170"},"PeriodicalIF":0.7,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097422","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":"A Single Relation Theory of Welfarist Social Evaluation","authors":"Robert Raschka","doi":"10.1016/j.jmateco.2025.103168","DOIUrl":"10.1016/j.jmateco.2025.103168","url":null,"abstract":"<div><div>The paper develops a systematic relational theory of social welfare evaluation. It is formulated in terms of a single difference relation capturing basic well-being comparisons between social alternatives. A new Fundamental Equity condition deals with trade-offs between individuals. It provides a unified rationale for different two-person conditions and identifies deep connections between seemingly distinct approaches to social evaluation. Dependent on the extent of interpersonal comparability, Strong Pareto and Fundamental Equity characterize Simple Majority Relation, Leximin, Utilitarianism, a level-based Borda Relation, and a new class of Equitable Welfarist Relations. They yield a general impossibility given weak incomparability. The analysis covers social evaluation under uncertainty, variable populations, and preference foundations of well-being comparisons. The relational theory is more general and more unified than the prevalent theory of Social Welfare Functionals. It does not use contestable inter-profile conditions and invariance requirements.</div></div>","PeriodicalId":50145,"journal":{"name":"Journal of Mathematical Economics","volume":"121 ","pages":"Article 103168"},"PeriodicalIF":0.7,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145011303","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}