nep-evo New Economics Papers
on Evolutionary Economics
Issue of 2010‒03‒06
five papers chosen by
Matthew Baker
City University of New York

  1. A Philosophical Perspective on Contemporary Evolutionary Economics By Geoffrey M. Hodgson
  2. Pure Saddle Points and Symmetric Relative Payoff Games By Duersch, Peter; Oechssler, Joerg; Schipper, Burkhard C
  3. From Shame to Game in One Hundred Years: An Economic Model of the Rise in Premarital Sex and its De-Stigmatization By Jesus Fernandez-Villaverde; Jeremy Greenwood; Nezih Guner
  4. Stability of Time Preferences By Meier, Stephan; Sprenger, Charles
  5. Unbeatable Imitation By Duersch, Peter; Oechssler, Joerg; Schipper, Burkhard C

  1. By: Geoffrey M. Hodgson
    Abstract: There has been a remarkable growth in evolutionary economics since the 1980s. But despite this outward success there has been inner disagreement on fundamental issues including the building blocks of evolutionary theory and the very meaning of ‘evolution’ itself. This essay provides a philosophical perspective on both the defining agreements and ongoing disputes within evolutionary economics. Its primary emphasis is on ontology. It shows that some major disputes derive not from incompatible propositions but the choice of different levels of analysis. A route toward reconciliation of different viewpoints is thus exposed.
    Keywords: Length 20 pages
    Date: 2010–02
  2. By: Duersch, Peter; Oechssler, Joerg; Schipper, Burkhard C
    Abstract: It is well known that the rock-paper-scissors game has no pure saddle point. We show that this holds more generally: A symmetric two-player zero-sum game has a pure saddle point if and only if it is not a generalized rock-paper-scissors game. Moreover, we show that every finite symmetric quasiconcave two-player zero-sum game has a pure saddle point. Further sufficient conditions for existence are provided. We apply our theory to a rich collection of examples by noting that the class of symmetric two-player zero-sum games coincides with the class of relative payoff games associated with symmetric two-player games. This allows us to derive results on the existence of a finite population evolutionary stable strategies.
    Keywords: symmetric two-player games; zero-sum games; Rock-Paper-Scissors; single-peakedness; quasiconcavity; finite population evolutionary stable strategy; increasing differences; decreasing differences; potentials; additive separability
    JEL: C72 C73
    Date: 2010–02–21
  3. By: Jesus Fernandez-Villaverde (University of Pennsylvania); Jeremy Greenwood (University of Pennsylvania); Nezih Guner (Universitat Autonoma de Barcelona)
    Abstract: Parents socialize their children about many things, including sex. Socialization is costly. It uses scarce resources, such as time and effort. Parents weigh the marginal gains from socialization against its costs. Parents at the lower end of the social-economic scale indoctrinate their daughters less than others about the perils of premarital sex, because the latter will lose less from an out-of-wedlock birth. Modern contraceptives have profoundly affected the calculus for instilling sexual mores, leading to a de-stigmatization of sex. As the odds of becoming pregnant from premarital sex decline there is less need to inculcate sexual mores. Technology affects culture.
    Keywords: contraception, culture, premarital sex, socialization, stigma, technological progress
    JEL: D58 J13 O15 N30
    Date: 2010–02
  4. By: Meier, Stephan (Columbia University); Sprenger, Charles (University of California, San Diego)
    Abstract: Individuals frequently face intertemporal decisions. For the purposes of economic analysis, the preference parameters assumed to govern these decisions are generally considered to be stable economic primitives. However, evidence on the stability of time preferences is notably lacking. In a large field study conducted over two years with about 1,400 individuals, time preferences are elicited using incentivized choice experiments. The aggregate distributions of discount factors and the proportion of present-biased individuals are found to be unchanged over the two years. At the individual level, the one year correlations in measured time preference parameters are found to be high by existing standards, though some individuals change their intertemporal choices potentially indicating unstable preferences. By linking time preference measures to tax return data, we show that identified instability is uncorrelated with socio-demographics and changes to income, future liquidity, employment and family composition.
    Keywords: experimental economics, time preferences, preference stability
    JEL: C93 D01 D11 D91
    Date: 2010–02
  5. By: Duersch, Peter; Oechssler, Joerg; Schipper, Burkhard C
    Abstract: We show that for many classes of symmetric two-player games, the simple decision rule "imitate-the-best" can hardly be beaten by any other decision rule. We provide necessary and sufficient conditions for imitation to be unbeatable and show that it can only be beaten by much in games that are of the rock-scissors-paper variety. Thus, in many interesting examples, like 2x2 games, Cournot duopoly, price competition, rent seeking, public goods games, common pool resource games, minimum effort coordination games, arms race, search, bargaining, etc., imitation cannot be beaten by much even by a very clever opponent.
    Keywords: Imitate-the-best; learning; symmetric games; relative payoffs; zero-sum games; rock-paper-scissors; finite population ESS; potential games; quasisubmodular games; quasisupermodular games; quasiconcave games; aggregative games
    JEL: D43 C73 C72
    Date: 2010–02–18

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