nep-evo New Economics Papers
on Evolutionary Economics
Issue of 2007‒06‒11
six papers chosen by
Matthew Baker
City University of New York

  1. Implications of Trust, Fear, and Reciprocity for Modeling Economic Behavior By James C. Cox; Klarita Sadiraj; Vjollca Vjollca
  2. Trust, Fear, Reciprocity, and Altruism: Theory and Experiment By James C. Cox
  3. Updating Validations and Stochastic Dynamics on Coordination By Hideki Fujiyama
  4. Direct Tests of Models of Social Preferences and a New Model By James C. Cox; Vjollca Sadiraj
  5. On the Emergence of Social Norms By Edward Cartwright
  6. Directed Altruism and Enforced Reciprocity in Social Networks: How Much is A Friend Worth? By Stephen Leider; Markus M. Möbius; Tanya Rosenblat; Quoc-Anh Do

  1. By: James C. Cox; Klarita Sadiraj; Vjollca Vjollca
    Abstract: This paper reports three experiments with triadic or dyadic designs. The experiments include the moonlighting game in which first-mover actions can elicit positively or negatively reciprocal reactions from second movers. First movers can be motivated by trust in positive reciprocity or fear of negative reciprocity, in addition to unconditional other-regarding preferences. Second movers can be motivated by unconditional other-regarding preferences as well as positive or negative reciprocity. The experimental designs include control treatments that discriminate among actions with alternative motivations. Data from our three experiments and a fourth one are used to explore methodological questions, including the effects on behavioral hypothesis tests of within-subjects vs. across-subjects designs, single-blind vs. double-blind payoffs, random vs. dictator first-mover control treatments, and strategy responses vs. sequential play.
    JEL: C70 C91 D63 D64
  2. By: James C. Cox
    Abstract: This paper describes central topics in our research program on social preferences. The discussion covers experimental designs that discriminate among alternative components of preferences such as unconditional altruism, positive reciprocity, trust (in positive reciprocity), negative reciprocity, and fear (of negative reciprocity). The paper describes experimental data on effects of social distance and decision context on reciprocal behavior and male vs. female and group vs. individual differences in reciprocity. The exposition includes experimental designs that provide direct tests of alternative models of social preferences and summarizes implications of data for the models. The discussion reviews models of other-regarding preferences that are and are not conditional on others’ revealed intentions and the implications of data for these models.
  3. By: Hideki Fujiyama
    Abstract: This work studies an equilibrium selection of infinitely repeated symmetric 2x2 coordination games that show a tension between Pareto efficiency and risk dominance, in which bounded rational agents adopt the following simple behavior rule: each agent has a valuation of actions, and chooses the highest one. Valuations are updated according to the sign of the difference between the current valuation and the realized payoff. By applying techniques from stochastic stable states (Kandori et al. 1993 and Young 1993), it is shown that the risk dominant outcome is selected; that is, it is realized more frequently in the long run.
  4. By: James C. Cox; Vjollca Sadiraj
    Abstract: Departures from "economic man" behavior in many games in which fairness is a salient characteristic are now well documented in the experimental economics literature. These data have inspired development of new models of social preferences incorporating inequality aversion and quasi-maximin preferences. We report experiments that provide direct tests of these social preference models. Data from the experiments motivate a new model of egocentric altruism. The model rationalizes data from our direct test experiments and data from experiments with proposer competition and responder competition. We discuss generalizations of the egocentric altruism model that incorporate agents’ intentions and thus provide a unified approach to modeling behavior in games both with and without reciprocal motivation.
    JEL: A12 A13 B49 C70 C91 D63
  5. By: Edward Cartwright
    Abstract: We consider a model of conformity that permits a non-conformist equilibrium and multiple conformist equilibria. Agents are assumed to behave according to a best reply learning dynamic. We details the conditions under which a social norm and conformity emerge. The emergence of conformity depends on the distribution of intrinsic preferences, the relative costs and benefits of conformity and the topology of agent interaction.
    Keywords: Social norms; conformity; best reply
    JEL: C7 D11
    Date: 2007–01
  6. By: Stephen Leider; Markus M. Möbius; Tanya Rosenblat; Quoc-Anh Do
    Abstract: We conduct field experiments in a large real-world social network to examine why decision makers treat friends more generously than strangers. Subjects are asked to divide surplus between themselves and named partners at various social distances, where only one of the decisions is implemented. In order to separate altruistic and future interaction motives, we implement an anonymous treatment where neither player is told at the end of the experiment which decision was selected for payment and a non-anonymous treatment where both players are told. Moreover, we include both games where transfers increase and decrease social surplus to distinguish between different future interaction channels including signaling one's generosity and enforced reciprocity, where the decision maker treats the partner to a favor because she can expect it to be repaid in the future. We can decompose altruistic preferences into baseline altruism towards any partner and directed altruism towards friends. Decision makers vary widely in their baseline altruism, but pass at least 50 percent more surplus to friends compared to strangers when decision making is anonymous. Under non-anonymity, transfers to friends increase by an extra 24 percent relative to strangers, but only in games where transfers increase social surplus. This effect increases with density of the network structure between both players, but does not depend on the average amount of time spent together each week. Our findings are well explained by enforced reciprocity, but not by signaling or preference-based reciprocity. We also find that partners' expectations are well calibrated to directed altruism, but that they ignore decision makers' baseline altruism. Partners with high baseline altruism have friends with higher baseline altruism and are therefore treated better.
    JEL: C73 C91 D64
    Date: 2007–05

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