nep-evo New Economics Papers
on Evolutionary Economics
Issue of 2025–12–08
nine papers chosen by
Matthew Baker, City University of New York


  1. Family Institutions and the Global Fertility Transition By Paula Eugenia Gobbi; Anne Hannusch; Pauline Rossi
  2. Collective Shocks and Social Preferences: A Global, Subnational Analysis By James Igoe Walsh; Alexander Kustov; Ivan Flores Martinez
  3. Expectation-enforcing strategies for repeated games By Nikos Dimou; Alex McAvoy
  4. "Don't Fall Behind": A Unified Framework of Dynastic Survival, Two-Stage Belief Error, and the Modern Involution Trap By Dong Yang
  5. Indigenous Circular Economies (IndCE): The Yurok Tribe, Regenerative Forest Management, and Tribal Sovereignty By Sindoni, Raffaele; Blake, Dawn; McCovey, Louisa; Carroo, Isaac; Gormley, Jasmine; Barker, Jake
  6. The Character of Spider-Man: Ethics and Greed in a General Equilibrium Model By Loureiro, Paulo Roberto Amorim
  7. Motivated Beliefs Under Delayed Uncertainty Resolution By Charlotte Cordes; Jana Friedrichsen; Simeon Schudy
  8. Cultural participation and the micro-dynamics of trust: Evidence from a large-scale field study By Giuseppe Attanasi; Giuseppe Ciccarone; Valentina Peruzzi
  9. A Bayesian approach to the Machina paradox By Mateus Joffily; Thijs van de Laar

  1. By: Paula Eugenia Gobbi; Anne Hannusch; Pauline Rossi
    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.
    Keywords: Fertility transition, culture, Family institutions
    JEL: J13
    Date: 2025–11–28
    URL: https://d.repec.org/n?u=RePEc:eca:wpaper:2013/397122
  2. By: James Igoe Walsh; Alexander Kustov; Ivan Flores Martinez
    Abstract: While some studies of conflicts, natural disasters, and economic setbacks find these negative collective shocks make people more prosocial, others find they reduce cooperation. These conflicting findings may be a consequence of focusing on a single shock type, a single preference measure, or a single regional or temporal context experiencing shocks. We address these limitations by creating and analyzing a new global dataset of collective shocks and social preferences at the subnational level. We then explore the potential differences in how various shocks (armed conflicts, natural disasters, economic downturns) relate to various social preferences (altruism, reciprocity, trust) and behaviors. Our preliminary analysis shows that, while exposure to armed conflicts or economic downturns does not systematically alter prosociality, exposure to natural disasters reduces some social preferences in the short term, reverting to baseline levels in the long term. By comparing local experiences globally, our project helps develop a nuanced view of how shocks influence preferences, with implications for cooperation and governance.
    Keywords: altruism, armed conflicts, natural disasters, reciprocity, trust
    JEL: D64 D74 Q54
    Date: 2025
    URL: https://d.repec.org/n?u=RePEc:hic:wpaper:444
  3. By: Nikos Dimou; Alex McAvoy
    Abstract: Originating in evolutionary game theory, the class of "zero-determinant" strategies enables a player to unilaterally enforce linear payoff relationships in simple repeated games. An upshot of this kind of payoff constraint is that it can shape the incentives for the opponent in a predetermined way. An example is when a player ensures that the agents get equal payoffs. While extensively studied in infinite-horizon games, extensions to discounted games, nonlinear payoff relationships, richer strategic environments, and behaviors with long memory remain incompletely understood. In this paper, we provide necessary and sufficient conditions for a player to enforce arbitrary payoff relationships (linear or nonlinear), in expectation, in discounted games. These conditions characterize precisely which payoff relationships are enforceable using strategies of arbitrary complexity. Our main result establishes that any such enforceable relationship can actually be implemented using a simple two-point reactive learning strategy, which conditions on the opponent's most recent action and the player's own previous mixed action, using information from only one round into the past. For additive payoff constraints, we show that enforcement is possible using even simpler (reactive) strategies that depend solely on the opponent's last move. In other words, this tractable class is universal within expectation-enforcing strategies. As examples, we apply these results to characterize extortionate, generous, equalizer, and fair strategies in the iterated prisoner's dilemma, asymmetric donation game, nonlinear donation game, and the hawk-dove game, identifying precisely when each class of strategy is enforceable and with what minimum discount factor.
    Date: 2025–11
    URL: https://d.repec.org/n?u=RePEc:arx:papers:2511.19828
  4. By: Dong Yang
    Abstract: We set out to solve a dual puzzle regarding reproductive strategies: The "Ancient vs. Modern" Puzzle (why pre-modern elites adopted a "Survival" strategy while modern elites adopt an "Anxiety" strategy) and the "Class Divide" Puzzle (why modern involution manifests as a U-shaped fertility pattern). We develop a unified computational framework (DP + Monte Carlo) that introduces Cognitive Heterogeneity across classes. Our Hybrid Model (M-H) posits that the poor act as "Rational Survivors" (M1 utility, Reality parameters), while the middle/rich act as "Biased Strivers" (M4b utility, Belief parameters). Our simulations yield three core findings. First, we confirm that the "Survival" strategy is objectively rational whenever risk exceeds a low threshold ($\sigma > 0.45$). Given that real-world risk is massive ($\sigma_{Real} \approx 4.9$), the modern "Quality" strategy is objectively fragile. Second, the trap for the Middle/Rich ($B \ge 200$) is driven by a "Two-Stage Belief Error": they are first "baited" by a Causal Error (underestimating risk) to enter the status game, and then "trapped" by a Marginal Error (underestimating returns) which triggers a stop in fertility. Third, the U-shape is driven by the cognitive divide. The Poor escape the trap by retaining a "Rational Survival" strategy in the face of real high risk. Conversely, the Aspirational Middle Class ($HC \approx 12, B \ge 200$) is uniquely trapped by their Biased Beliefs. Their high competence raises their dynastic reference point ($R$) to a level where, under perceived low returns, restricting fertility to $N=1$ becomes the only rational choice within their biased belief system.
    Date: 2025–11
    URL: https://d.repec.org/n?u=RePEc:arx:papers:2511.19017
  5. By: Sindoni, Raffaele; Blake, Dawn; McCovey, Louisa; Carroo, Isaac; Gormley, Jasmine; Barker, Jake
    Abstract: In this research, we present the Indigenous Circular Economy (IndCE); not as a novel framework, but as an enduring system of stewardship, resilience, and relationality practiced by Indigenous communities for generations. As Indigenous (Yurok/Hoopa) and non-Indigenous co-authors, we draw on historical analysis, forest science, Yurok oral tradition, and Traditional Ecological Knowledge (TEK) to demonstrate how IndCE repairs the ecological and cultural harm of capitalist economies by weaving together forest health with human health. Through a case study of the Yurok Tribe in Northern California, we highlight how IndCE is not just a cultural or local economic alternative. It is a paradigm shift away from economic perspectives that ignore culture, history, land, and non-human & human relationships. The Yurok stewardship practices that support its IndCE (e.g. Good Fire) provide a slew of benefits: wildfire risk mitigation, ecosystem restoration, economic revitalization, and cultural resilience. The Yurok case reveals the urgency of legitimizing and resourcing Indigenous-led ecological governance. We identify persistent policy and funding barriers that undermine this work and offer concrete paths forward to support it. This paper contributes to broader debates on sustainable economics, Indigenous rights, and community-led conservation. It also raises critical questions for non-Indigenous communities about how some state systems may sometimes obstruct, rather than support, regenerative land stewardship, cultural continuity, and ecological care. The Yurok model shows that another type of economy is not only possible; it already exists.
    Date: 2025–11–25
    URL: https://d.repec.org/n?u=RePEc:osf:socarx:jznrf_v1
  6. By: Loureiro, Paulo Roberto Amorim
    Abstract: This paper develops a general equilibrium model in which ethics and greed coexist as opposing forces shaping social and economic stability. Individuals choose be- tween legal and illicit effort, while ethical agents internalize a moral cost, and the government sets enforcement and penalties. The dynamic interaction between moral restraint, institutional enforcement, and social respect determines the aggregate equilibrium. The model shows that, in the absence of virtue or enforcement, greed dominates and equilibrium collapses; yet, when moral costs or public integrity poli- cies rise, the economy converges to a stable and more equitable state. Mathematical stability is derived from Jury’s conditions, and an empirical strategy is proposed to test these mechanisms using crime, enforcement, and social capital data. Ultimately, morality emerges as an endogenous economic variable—an efficient complement to law, rather than its substitute.
    Keywords: Ethics, Greed, General Equilibrium, Crime, Enforcement, Welfare Policy, Spider-Man, Moral Economics
    JEL: D13 D5 I38 J12 K42
    Date: 2025–05–05
    URL: https://d.repec.org/n?u=RePEc:pra:mprapa:126613
  7. By: Charlotte Cordes; Jana Friedrichsen; Simeon Schudy
    Abstract: Experimental studies show that individuals update beliefs about ego-relevant information optimistically when they expect no resolution of uncertainty but neutrally when their ability is revealed immediately. This paper studies belief updating and the role of motivated memory when feedback is delayed but eventually disclosed. In a longitudinal experiment, participants receive noisy signals about their relative performance in a IQ-related task (Raven matrices) and learn their true rank four weeks later. Across subjects, belief updating is asymmetric: unfavorable signals are weighted less than favorable signals. Further, we identify motivated memory among participants who view the task as ego-relevant.
    Keywords: motivated beliefs, feedback, memory, Anticipatory utility, motivated cognition, uncertainty
    JEL: C91 D03 D81 D83 D84
    Date: 2025
    URL: https://d.repec.org/n?u=RePEc:ces:ceswps:_12286
  8. By: Giuseppe Attanasi; Giuseppe Ciccarone; Valentina Peruzzi
    Abstract: This paper investigates how collective cultural participation shapes the micro-dynamics of trust formation and its short-term social and economic effects. Using unique microdata from a long-term field study of collective cultural participation, comprising more than 13, 000 face-to-face interviews, we examine whether engagement in shared artistic experiences enhances instantaneous social capital, defined as a temporary yet socially meaningful increase in interpersonal trust. Results show that emotional and bodily participation in collective performances significantly increases the likelihood of reporting higher trust toward others. This situational trust, in turn, predicts a greater willingness to volunteer and higher local spending. The findings highlight that cultural events can act as catalysts of both social cohesion and local economic vitality, even within short-lived, non-institutional settings.
    Keywords: social capital; trust; cultural participation; field study; prosocial behavior; local development
    JEL: Z13 D91 D64 O18 C83
    Date: 2025–11
    URL: https://d.repec.org/n?u=RePEc:sap:wpaper:wp266
  9. By: Mateus Joffily (CNRS, Université Lumière Lyon 2, Université Jean Monnet Saint-Etienne, emlyon business school, GATE, 69007 Lyon, France); Thijs van de Laar (Department of Electrical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands)
    Abstract: Variants of the Ellsberg urn experiments introduced by Machina (Am. Econ. Rev., 99(1), 385-392, 2009) have challenged several prominent models of ambiguity aversion. We show that our Bayesian hierarchical model - originally developed to explain Ellsberg-type preferences - also captures the ambiguity preferences observed in Machina's reflection example. Our findings indicate that ambiguity aversion in both the Ellsberg and Machina paradoxes can be attributed to pessimistic prior beliefs about unobserved outcomes. Moreover, the model predicts an asymmetric pattern of preferences across intermediate payoff levels in the reflection example: ambiguity aversion is stronger when the intermediate payoff lies closer to the worst outcome, while the opposite holds for ambiguity-seeking preferences.
    Keywords: Machina Paradox; Ambiguity Aversion; Bayesian Modeling
    JEL: C63 D81 D91
    Date: 2025
    URL: https://d.repec.org/n?u=RePEc:gat:wpaper:2525

This nep-evo issue is ©2025 by Matthew Baker. It is provided as is without any express or implied warranty. It may be freely redistributed in whole or in part for any purpose. If distributed in part, please include this notice.
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