nep-evo New Economics Papers
on Evolutionary Economics
Issue of 2026–03–09
six papers chosen by
Matthew Baker, City University of New York


  1. Family Institutions and the Global Fertility Transition By Paula E Gobbi; Anne Hannusch; Pauline Rossi
  2. Cultural Transmission, Property Rights, and Treatment of the Elderly By Matthew J. Baker; Joyce P. Jacobsen
  3. Selection and evolutionary growth in pre-industrial Germany By Ohler, Johann
  4. How does AI distribute the pie? Large Language Models and the Ultimatum Game By Douglas K.G. Araujo; Harald Uhlig
  5. Do Socioeconomic Disparities Shape Norm Enforcement? By Irving Argaez Corona; Béatrice Boulu-Reshef; Jean-Christophe Vergnaud
  6. Natural disasters and cooperation under diversity: Evidence from Hurricane Harvey By Balán, Pablo; Pinto, Pablo M.; Vallejo, Agustín

  1. By: Paula E Gobbi (ULB - Université libre de Bruxelles = Free University of Brussels); Anne Hannusch (Universität Bonn = University of Bonn); Pauline Rossi (CREST - Centre de Recherche en Économie et Statistique - ENSAI - Ecole Nationale de la Statistique et de l'Analyse de l'Information [Bruz] - Groupe ENSAE-ENSAI - Groupe des Écoles Nationales d'Économie et Statistique - X - École polytechnique - IP Paris - Institut Polytechnique de Paris - ENSAE Paris - École Nationale de la Statistique et de l'Administration Économique - Groupe ENSAE-ENSAI - Groupe des Écoles Nationales d'Économie et Statistique - IP Paris - Institut Polytechnique de Paris - CNRS - Centre National de la Recherche Scientifique, X - École polytechnique - IP Paris - Institut Polytechnique de Paris, IP Paris - Institut Polytechnique de Paris)
    Abstract: Much of the observed cross-country variation in fertility aligns with the predictions of classic theories of the fertility transition: countries with higher levels of human capital, higher GDP per capita, or lower mortality rates tend to exhibit lower fertility. However, when examining changes within countries over the past 60 years, larger fertility declines are only weakly associated with greater improvements in human capital, per capita GDP, or survival rates. To understand why, we focus on the role of family institutions, particularly marriage and inheritance customs. We argue that, together with the diffusion of cultural norms, they help explain variations in the timing, speed and magnitude of the fertility decline. We propose a stylized model integrating economic, health, institutional and cultural factors to study how these factors interact to shape fertility transition paths. We find that family institutions can mediate the effect of economic development by constraining fertility responses.
    Date: 2026–02–01
    URL: https://d.repec.org/n?u=RePEc:hal:journl:hal-05496893
  2. By: Matthew J. Baker (Department of Economics, Hunter College and the Graduate Center, CUNY); Joyce P. Jacobsen (Department of Economics, Hobart and William Smith Colleges, and Wesleyan University)
    Abstract: We study how property rights over land, capital, and output interact with cul-tural transmission to determine the welfare of the elderly. In our model, respect for the elderly emerges endogenously: adults transmit norms of care to children, which children later reciprocate when they become adults. We compare regimes of insecure rights over produced goods with secure rights over productive resources, showing that both can sustain elderly well-being through distinct channels. By distinguishing be-tween property rights to outputs and to inputs—and further between fixed and created resources—we uncover nonlinear interactions between cultural transmission, property institutions, and production technologies, and a general curvilinear pattern where the elderly are relatively better off compared to the middle-aged in either an insecure prop-erty right (i.e., common resources) regime or a high productive property rights regime relative to intermediate cases. Ethnographic evidence illustrates these mechanisms and helps explain cross-societal variation in elderly support. The model also demonstrates how demographic, technological, and policy changes can alter the conditions for elderly well-being across stages of development.
    Keywords: treatment of the elderly, overlapping generations, property rights, cultural transmission, intergenerational transfers
    JEL: E21 D15 J14 O15 Z13
    Date: 2026–01
    URL: https://d.repec.org/n?u=RePEc:wes:weswpa:2026-002
  3. By: Ohler, Johann
    Abstract: Evolutionary growth theory (i.e., Galor and Moav (2002) and Clark (2007)) posits that natural selection set the stage for modern growth. I leverage micro-data from historical Germany to assess the viability of the selection mechanisms. I estimate fertility differentials and the inter-generational transmission of SES. High status couples, proxied by occupation, had 1-2 additional children, and SES was strongly heritable. To explore whether these parameters induce selection, I simulate an overlapping generation model of fertility choice and status transmission. The German parameters do not enable Clark’s survival of the richest, whereas Galor and Moav’s selection on quality can arise if the returns to investing in child quality are sufficiently large. Monte Carlo simulations extend the analysis beyond Germany. Survival of the richest requires exceptionally high coefficients of transmission (≈0.87), and selection on quality emerges whenever returns to quality investments translate into higher fertility. Both depend on the strong heritability of the growth-complementary traits.
    Keywords: socioeconomic status; fertility; inter-generational mobility; endogenous growth theory; survival of the riches; historical demography
    JEL: O40 J12 J13 J62 N33
    Date: 2026–01
    URL: https://d.repec.org/n?u=RePEc:ehl:wpaper:137404
  4. By: Douglas K.G. Araujo (Banco Central do Brasil); Harald Uhlig (University of Chicago, CEPR and NBER)
    Abstract: As Large Language Models (LLMs) are increasingly tasked with autonomous decisionmaking, understanding their behavior in strategic settings is crucial. We investigate the choices of various LLMs in the Ultimatum Game, a setting where human behavior notably deviates from theoretical rationality. We conduct experiments varying the stake size and the nature of the opponent (Human vs. AI) across both Proposer and Responder roles. Three key results emerge. First, LLM behavior is heterogeneous but predictable when conditioning on stake size and player types. Second, while some models approximate the rational benchmark and others mimic human social preferences, a distinct “altruistic†mode emerges where LLMs propose hyper-fair distributions (greater than 50%). Third, LLM Proposers forgo a large share of total payoff, and an even larger share when the Responder is human. These findings highlight the need for careful testing before deploying AI agents in economic settings.
    Keywords: Ultimatum Game, LLM, AI Agents, Behavioral Economics, Algorithmic Decision Making
    JEL: C70 C90 D91
    Date: 2026
    URL: https://d.repec.org/n?u=RePEc:bfi:wpaper:2026-29
  5. By: Irving Argaez Corona (CES - Centre d'économie de la Sorbonne - UP1 - Université Paris 1 Panthéon-Sorbonne - CNRS - Centre National de la Recherche Scientifique); Béatrice Boulu-Reshef (THEMA - Théorie économique, modélisation et applications - CNRS - Centre National de la Recherche Scientifique - CY - CY Cergy Paris Université); Jean-Christophe Vergnaud (CES - Centre d'économie de la Sorbonne - UP1 - Université Paris 1 Panthéon-Sorbonne - CNRS - Centre National de la Recherche Scientifique)
    Abstract: We investigate how socioeconomic disparities shape the enforcement of norms when observing third-party dishonesty. In an online Die-under-the-Cup (DUTC) experiment with a socioeconomically and geographically diverse sample of 720 participants from the French population, observers repeatedly evaluate reports from socioeconomically close and distant counterparts and can punish or reward them without affecting their own payoffs. We classify participants into three socioeconomic tiers using (i) a contextual measure based on average income in the locality of residence and (ii) a relative measure capturing individual income relative to the locality average. To summarise dishonest reporting patterns in this private-report environment, we introduce an observer-level proxy of suspicious reports. Results show that enforcement responds sharply to this proxy, as observers punish more and reward less as suspicion rises. Whether enforcement is socially selective depends on how distance is measured. Under the contextual measure, we find little evidence that close and distant counterparts are treated differently at comparable suspicion levels. Under the relative measure, selectivity emerges through responsiveness: punishment escalates more and rewards drop more strongly as suspicion increases when counterparts are socioeconomically distant. Finally, decomposing pairings by socioeconomic tiers reveals asymmetric enforcement along the hierarchy: holding suspicion constant, observers punish more and reward less when the counterpart is below them in socioeconomic status. In sum, the paper shows that how we measure socioeconomic distance is relevant for norm enforcement—highlighting a channel through which enforcement can reproduce inequality.
    Abstract: Nous étudions comment les disparités socioéconomiques influencent l'application des normes lorsqu'un individu observe la malhonnêteté d'un tiers. Dans une expérience en ligne de type « Die-under-the-Cup » (DUTC), menée auprès d'un échantillon de 720 participants de la population française, divers sur les plans socioéconomique et géographique, les observateurs évaluent à plusieurs reprises les déclarations de partenaires socialement proches ou socialement éloignés sur le plan socioéconomique, et peuvent les punir ou les récompenser sans que cela n'affecte leurs propres gains. Nous classons les participants en trois catégories socioéconomiques à l'aide (i) d'une mesure contextuelle fondée sur le revenu moyen de la localité de résidence et (ii) d'une mesure relative capturant le revenu individuel par rapport à la moyenne de la localité. Afin de résumer les schémas de déclaration malhonnête dans cet environnement de déclaration privée, nous introduisons un indicateur au niveau de l'observateur de déclarations suspectes. Les résultats montrent que l'application des normes réagit fortement à cet indicateur : les observateurs punissent davantage et récompensent moins à mesure que la suspicion augmente. Le caractère socialement sélectif de l'application des normes dépend toutefois de la façon dont la distance est mesurée. Avec la mesure contextuelle, nous trouvons peu d'éléments indiquant que les partenaires proches et éloignés sont traités différemment à niveaux de suspicion comparables. Avec la mesure relative, la sélectivité apparaît via la réactivité : la punition s'intensifie davantage et les récompenses diminuent plus fortement, à mesure que la suspicion augmente, lorsque les partenaires sont socioéconomiquement éloignés. Enfin, en décomposant les appariements par catégories socioéconomiques, nous mettons en évidence une application asymétrique le long de la hiérarchie : à suspicion constante, les observateurs punissent davantage et récompensent moins lorsque le partenaire est situé plus bas qu'eux dans la hiérarchie socioéconomique. En somme, l'article montre que la manière dont on mesure la distance socioéconomique est déterminante pour l'application des normes, et met en lumière un canal par lequel cette application peut contribuer à reproduire les inégalités.
    Keywords: socioeconomic status, Social closeness, norm enforcement, observability, third-party punishment, third-party reward, income levels, Socioeconomic inequality
    Date: 2025–12–01
    URL: https://d.repec.org/n?u=RePEc:hal:cesptp:hal-05368602
  6. By: Balán, Pablo; Pinto, Pablo M.; Vallejo, Agustín
    Abstract: How does diversity affect cooperation after natural disasters? Drawing on an original survey of Houston-area households and two survey experiments, we find that diversity is associated with lower levels of impersonal cooperation-beyond family and friends-before natural disasters and with lower cooperation both before and after disasters. In affected areas, households in more diverse tracts report receiving less help and express lower support for recovery policies. In a policy experiment, affected respondents typically favor more costly recovery measures, but this preference weakens in high-diversity areas. A second experiment uncovers strong post-disaster ingroup biases along partisan and religious lines, while shared membership in civic associations emerges as a critical facilitator of cooperation in diverse settings. Taken together, these findings demonstrate that diversity can impede post-disaster cooperation and illuminate how social identities shape cooperation and recovery efforts.
    Date: 2025
    URL: https://d.repec.org/n?u=RePEc:zbw:cbscwp:337494

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