nep-evo New Economics Papers
on Evolutionary Economics
Issue of 2023‒05‒29
six papers chosen by
Matthew Baker
City University of New York

  1. GPT Agents in Game Theory Experiments By Fulin Guo
  2. Cooperation and Cognition in Social Networks By Edoardo Gallo; Joseph Lee; Yohanes Eko Riyanto; Erwin Wong
  3. Human Brain Evolution in a Malthusian Economy By Chu, Angus C.
  4. Homo Moralis and regular altruists II By Aslihan Akdeniz; Christopher Graser; Matthijs van Veelen
  5. Traditional Institutions in Modern Times: Dowries as Pensions When Sons Migrate By Natalie Bau; Gaurav Khanna; Corinne Low; Alessandra Voena
  6. Social Preferences and Deliberately Stochastic Behavior By Yosuke Hashidate; Keisuke Yoshihara

  1. By: Fulin Guo
    Abstract: This paper explores the potential of using Generative Pre-trained Transformer (GPT)-based agents as participants in strategic game experiments. Specifically, I focus on the finitely repeated ultimatum and prisoner's dilemma games, two well-studied games in economics. I develop prompts to enable GPT agents to understand the game rules and play the games. The results indicate that, given well-crafted prompts, GPT can generate realistic outcomes and exhibit behavior consistent with human behavior in certain important aspects, such as positive relationship between acceptance rates and offered amounts in the ultimatum game and positive cooperation rates in the prisoner's dilemma game. Some differences between the behavior of GPT and humans are observed in aspects like the evolution of choices over rounds. I also study two treatments in which the GPT agents are prompted to either have social preferences or not. The treatment effects are evident in both games. This preliminary exploration indicates that GPT agents can exhibit realistic performance in simple strategic games and shows the potential of using GPT as a valuable tool in social science research.
    Date: 2023–05
  2. By: Edoardo Gallo; Joseph Lee; Yohanes Eko Riyanto; Erwin Wong
    Abstract: Social networks can sustain cooperation by amplifying the consequences of a single defection through a cascade of relationship losses. Building on Jackson et al. (2012), we introduce a novel robustness notion to characterize low cognitive complexity (LCC) networks - a subset of equilibrium networks that imposes a minimal cognitive burden to calculate and comprehend the consequences of defection. We test our theory in a laboratory experiment and find that cooperation is higher in equilibrium than in non-equilibrium networks. Within equilibrium networks, LCC networks exhibit higher levels of cooperation than non-LCC networks. Learning is essential for the emergence of equilibrium play.
    Date: 2023–05
  3. By: Chu, Angus C.
    Abstract: This study develops a Malthusian growth model with heterogeneous agents and natural selection to explore the evolution of human brain size. We find that if the cognitive advantage of a larger brain dominates its higher metabolic costs, then the average brain size increases over time, which is consistent with the rising trend in human brain size that started over 2 million years ago. Furthermore, an improvement in hunting-gathering productivity gives rise to a larger optimal brain size in human evolution. Finally, as the average brain size increases, the average level of hunting-gathering productivity also rises, generating a positive feedback loop.
    Keywords: Natural selection; brain size evolution; Malthusian growth theory
    JEL: N1 O13 Q56
    Date: 2023–04
  4. By: Aslihan Akdeniz (University of Amsterdam); Christopher Graser (University of Amsterdam); Matthijs van Veelen (University of Amsterdam)
    Abstract: Alger and Weibull (2013) ask the question whether a combination of assortative matching and incomplete information leads to the evolution of moral or altruistic preferences. Their central result states that Homo Hamiltonenis – a type that has moral preferences with a morality parameter equal to the level of assortment – is evolutionarily stable, while preferences that lead to different behaviour are unstable. Together with their claim that altruistic and moral preferences differ sharply, this suggests that moral preferences tend to beat altruistic ones in evolutionary competition. We show that this is not true. First of all, we show that there is a loophole in the definition of evolutionary stability, allowing for Homo Hamiltonensis to satisfy the definition when the set of equilibria is empty, and their equilibrium behaviour is not determined. If we try to close this loophole, by allowing for mixing, or by allowing for asymmetric equilibria, we find that there are two options. With the first approach, the differences in behaviour between Homo Hamiltonensis and regular altruists can be substantial, but as soon as the difference appears, Homo Hamiltonensis can be invaded, and regular altruists win in direct competition. With the second way of allowing for mixing, or coordination on asymmetric equilibria, Homo Hamiltonensis cannot be invaded, but then the difference in behaviour all but disappears, as all equilibria between Homo Hamiltonensis are also equilibria between regular altruists. Classification-JEL:
    Keywords: Altruism, morality, evolution, assortment, incomplete information.
    Date: 2023–05–08
  5. By: Natalie Bau; Gaurav Khanna; Corinne Low; Alessandra Voena
    Abstract: This paper examines whether an important cultural institution in India - dowry - can enable male migration by increasing the liquidity available to young men after marriage. We hypothesize that one cost of migration is the disruption of traditional elderly support structures, where sons live near their parents and care for them in their old age. Dowry can attenuate this cost by providing sons and parents with a liquid transfer that eases constraints on income sharing. To test this hypothesis, we collect two novel datasets on property rights over dowry among migrants and among families of migrants. Net transfers of dowry to a man's parents are common but far from universal. Consistent with using dowry for income sharing, transfers occur more when sons migrate, especially when they work in higher-earning occupations. Nationally representative data confirms that migration rates are higher in areas with stronger historical dowry traditions. Finally, exploiting a large-scale highway construction program, we show that men from areas with stronger dowry traditions have a higher migration response to reduced migration costs. Despite its potentially adverse consequences, dowry may play a role in facilitating migration and therefore, economic development.
    JEL: J12 J61 O12
    Date: 2023–04
  6. By: Yosuke Hashidate; Keisuke Yoshihara
    Abstract: This study proposes a tractable stochastic choice model to identify motivations for prosocial behavior, and to explore alternative motivations of deliberate randomization beyond ex-ante fairness concerns. To represent social preferences, we employ an additively perturbed utility model consisting of the sum of expected utility and a nonlinear cost function, where the utility function is purely selfish while the cost function depends on social preferences. Using the cost function, we study stochastic choice patterns to distinguish between stochastic inequity-averse behavior and stochastic shame-mitigating behavior. Moreover, we discuss how our model can complement recent experimental evidence of ex-post and ex-ante fairness concerns.
    Date: 2023–04

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