nep-evo New Economics Papers
on Evolutionary Economics
Issue of 2014‒11‒01
four papers chosen by
Matthew Baker
City University of New York

  1. Physiological Constraints and Comparative Economic Development By Carl-Johan Dalgaard; Holger Strulik
  2. Social Comparison and Peer effects with Heterogeneous Ability By Aurélie BONEIN
  3. Exploring the Population Implications of Male Preference When the Sex Probabilities at Birth Can Be Altered By Frank T. Denton; Byron G. Spencer
  4. Walled Cities in Late Imperial China By Yannis Ioannides; Junfu Zhang

  1. By: Carl-Johan Dalgaard (Department of Economics, Copenhagen University); Holger Strulik (Department of Economics, University of Goettingen)
    Abstract: It is a well known fact that economic development and distance to the equator are positively correlated variables in the world today. It is perhaps less well known that as recently as 1500 C.E. it was the other way around. The present paper provides a theory of why the "latitude gradient" seemingly changed sign in the course of the last half millennium. In particular, we develop a dynamic model of economic and physiological development in which households decide upon the number and nutrition of their offspring. In this setting we demonstrate that relatively high metabolic costs of fertility, which may have emerged due to positive selection towards greater cold tolerance in locations away from the equator, would work to sti fle economic development during pre-industrial times, yet allow for an early onset of sustained growth. As a result, the theory suggests a reversal of fortune whereby economic activity gradually shifts away from the equator in the process of long-term economic development.
    Keywords: long-run growth, evolution, nutrition, fertility, education, comparative development.
    JEL: O11 I12 J13
    Date: 2014–10–08
  2. By: Aurélie BONEIN (CREM UMR CNRS 6211, University of Rennes 1, France)
    Abstract: Whether and how the observability of a coworker’s effort influences an employer’s wage decisions and workers’ effort decisions is a central issue for labor organizations. We conduct an experiment using a three-person gift-exchange game to investigate this matter in the context of wage transparency and heterogeneous abilities. We find that showing a coworker’s effort increases both wages and the difference in wages between two heterogeneously skilled workers when the more able worker is observed. The knowledge of a coworker’s effort increases the level of reciprocity exhibited by observed workers (peer effects), whereas it reduces that exhibited by workers who are observers. Overall, displaying coworker’s effort has a beneficial effect on reciprocity. Regardless of their ability, workers exert levels of effort that are positively related to those of their coworkers. This strategic complementarity of efforts is partially explained by inequity aversion.
    Keywords: Heterogeneous ability, Gift-exchange game, Social comparison, Peer effect, Reciprocity
    JEL: C91 D03 J24 J31 J82
    Date: 2014–08
  3. By: Frank T. Denton; Byron G. Spencer
    Abstract: OBJECTIVE: The paper explores the population effects of male preference stopping rules and of alternative combinations of fertility rates and male-biased birth sex ratios. METHODS: The “laboratory” is a closed, stable population with five age groups and a dynamic process represented by a compact Leslie matrix. The new element is sex-selective abortion. We consider nine stopping rules, one with no male preference, two with male preference but no abortion, and six with male preference and the availability of abortion to achieve a desired number of male births. We calculate the probability distribution over the number of births and number of male births for each rule and work out the effects at the population level if the rule were adopted by all women bearing children. We then assess the impact of alternative combinations of fertility rates and male-biased sex ratios on the population. RESULTS: In the absence of sex-selective abortion, stopping rules generally have no effect on the male/female birth proportions in the population, although they can alter the fertility rate, age distribution, and rate of growth. When sex-selective abortion is introduced the effect on male/female proportions may be considerable, and other effects quite different as well. The contribution of this paper is the quantification of effects that might have been predictable in general but which require model-based calculations to see how large they could be. As the paper shows, they could in fact be very large; a population in which sex-selective abortion was widely practised could look quite different from what it would otherwise be.
    Keywords: birth sex probabilities, male preference, population implications
    Date: 2014–10
  4. By: Yannis Ioannides; Junfu Zhang
    Abstract: For thousands of years, the Chinese and many other nations around the workd built defensive walls around their cities. This phenomenon is not well understood from an economic perspective. To rationalize the existence of city walls, we propose a simple model that relates the deimesions of city walls to a set of economic variables. Guided by this model, we conduct an empirical alyalysis using hand-collected and previously unused data on city walls in the Ming (1368-1644) and Qing (1644-1911) Dynasties. Consistent with the model, we find that the circumference of a city wall is positively correlated with population size in the jurisdiction and that frontier cities subject to a higher probability of attack tended to have stronger city walls. Since a city wall imposes a physical boundary around a city, the land area inside the city wall provides a natural proxy of city size. We examine the physical size distribution of walled cities in late imperial Chian. We find that city sizes above a certain cutoff follow Zipf's law, although the Zipf coefficient is sensitive to the choice of the cutoff point. This result complements findigs in the existing literature that focuses almost exclusively on the population size distribution of cities.
    Keywords: City walls, Pareto distribution, Zipf's law, power law, China
    JEL: R12

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