Easter Island’s collapse: a tale of a population race

The Easter Island tragedy has become an allegory for ecological catastrophe and a warning for the future. In the economic literature the collapse is usually attributed to irrational or myopic behavior in the context of a fragile ecosystem. In this paper we propose an alternative story involving non-cooperative bargaining between clans to share the crop. Each clan’s bargaining power depends on its threat level when fighting a war. The biggest group has the highest probability of winning. A clan’s fertility is determined ex ante by each group. In the quest for greater bargaining power, each clan’s optimal size depends on that of the other clan, and a population race follows. This race may exhaust the natural resources and lead to the ultimate collapse of the society. In addition to well-known natural factors, the likelihood of a collapse turns out to be greater when the cost of war is low, the probability of succeeding in war is highly responsive to the number of fighters, and the marginal return to labor is high. We analyze whether these factors can account for the difference between Easter and Tikopia Islands. The paper also makes a methodological contribution in that it is the first fertility model to include strategic complementarities between groups’ fertility decisions.      

Assignment models and reneging

Summary. We consider a non-cooperative assignment model where we show that any subgame perfect equilibrium is stable, and that an appropriate refinement criterion leads to the p-optimal outcome. We then consider a model with reneging and derive some interesting properties of this game. We show that in this case ‘unraveling’ may occur. Furthermore, the resulting outcome can be either stable, or unstable. Received: July 1, 1997; revised version: May 30, 1998     

Harvesting in an integrated general equilibrium model

Harvesting of prey biomass is analyzed in an integrated ecological-economic system whose submodels, a predator–prey ecosystem and a simple economy, are microfounded dynamic general equilibrium models. These submodels are interdependent because the ecosystem responds to harvesting—through the reactions of optimizing individual organisms—by changing the provision of public ecosystem services to consumers. General analytical results are derived regarding the impact of harvesting policies on short-run equilibria of both submodels, on population dynamics, and on stationary states of the integrated model. A key insight is that prey biomass carries a positive ecosystem price which needs to be added as a tax mark-up to the economic price of harvested biomass to attain allocative efficiency. Further information on the dynamics is gained by resorting to numerical analysis of the policy regimes of zero harvesting, laissez-faire harvesting and efficient harvesting.

It “... is a matter of weighing costs and benefits of taking action, whether the action is the “inert” one of leaving resources alone in order to conserve them, or whether it involves exploiting a resource ... for so-called material ends”. Pearce (1976, p. 320)

Helpful comments from an anonymous referee are gratefully acknowledged. Remaining errors are the authors’ sole responsibility.     

Evolutionary stability in repeated extensive games played by finite automata

We discuss the emergence of cooperation in repeated Trust Mini-Games played by finite automata. Contrary to a previous result obtained by Piccione and Rubinstein (1993), we first prove that this repeated game admits two Nash equilibria, a cooperative and a non-cooperative one. Second, we show that the cooperative equilibrium is the only (cyclically) stable set under the so-called best response dynamics.     

Capital growth in a global warming model: will China and India sign a climate treaty?

Global warming is now recognized as a significant threat to sustainable development on an international scale. One of the key challenges in mounting a global response to it is the seeming unwillingness of the fastest growing economies such as China and India to sign a treaty that limits their emissions. The aim of this paper is to examine the differential incentives of countries on different trajectories of capital growth. A benchmark dynamic game to study global warming, introduced in Dutta and Radner (J Econ Behav Organ, 2009), is generalized to allow for exogenous capital accumulation. It is shown that the presence of capital exacerbates the “tragedy of the common”. Furthermore, even with high discount factors, the threat of reverting to the inefficient “tragedy” equilibrium is not sufficient to deter the emissions growth of the fastest growing economies—in contrast to standard folk theorem like results. However, foreign aid can help. If the slower growth economies—like the United States and Western Europe—are willing to make transfers to China and India, then the latter can be incentivized to cut emissions. Such an outcome is Pareto improving for both slower and faster growth economies.     

Environmental versus Human-Induced Scarcity in the Commons: Do They Trigger the Same Response?

We study appropriation strategies in common pool resources where extinction is a credible threat. Here we present an experimental study of the appropriation of common pool resources in a dynamic setting where resource availability depends on the initial environmental characteristics of the common resource and on human-induced resource depletion due to users’ appropriation patterns. Our results show that initial resource scarcity limits appropriation by inducing an initial caution among users that persists throughout of the game. Additionally, we find that subjects restrain their appropriation strategies when scarcity increases. However, this concern for resource scarcity is not enough to prevent resource depletion. Agents do not counteract the previous rounds’ appropriation strategies but follow the appropriation trend. High appropriation levels are followed by higher appropriation strategies, thus promoting the well known tragedy of the commons. Often concern for resource preservation is not great enough to limit appropriation.      

Sequential Markets: An Experimental Investigation of Clower's Dual-Decision Hypothesis

Countless experimental studies have shown that markets converge quickly and efficiently to the competitive outcome under many trading institutions, particularly the double auction mechanism. This creates difficulties for Keynesian stories of unemployment creation—which suggest a noncompetitive outcome in an essentially competitive world. Such stories were popular in the late 1960s and 1970s. One of these stories—the dual decision hypothesis of Clower—was seen then as the beginning of a story of unemployment. This article reports the results of an experiment designed to test this hypothesis. Specifically, we set up an experiment in which there are two sequential double-auction markets, in the first of which one good (labour) is traded, after which the second market (goods) is opened and the second good traded. We compare the outcome of our experiment with that of the competitive theory. One general finding is that not enough trade takes place in the two markets. In other words, the usual finding that competitive equilibrium is achieved in double-auction markets is not replicated in this sequential setting. This revised version was published online in August 2006 with corrections to the Cover Date.     

草原生态补偿与可持续发展研究——以呼伦贝尔草原的实践为例

草原生态补偿是促进农牧民增收和草原地区经济发展的重要措施,该机制的建立,从制度上可以保证农牧民的生计,从行为上可以引导农牧民调整草原畜牧业生产方式,实现草原生态环境协调可持续发展。草原生态补偿应落实好草原承包制度,要充分考虑到合理载畜量,在补偿方面以草畜平衡、管护、燃料替代等方面为重点,逐步建立和完善草原生态补偿制度体系。草原生态补偿体系在完善过程中要重点抓好落实草原保护制度,加强后期保护工作力度;积极推行草畜平衡制度,严格控制载畜量,限制超载放牧,规范草地利用制度,保护草原天然植被;加大草原地区投资力度,保障草原地区生态经济可持续发展;建立健全草原监理机构,依法行政保护草原资源;强化牧民的草原环保意识及其文化教育和技能培训。     

The online laboratory: conducting experiments in a real labor market

Online labor markets have great potential as platforms for conducting experiments. They provide immediate access to a large and diverse subject pool, and allow researchers to control the experimental context. Online experiments, we show, can be just as valid—both internally and externally—as laboratory and field experiments, while often requiring far less money and time to design and conduct. To demonstrate their value, we use an online labor market to replicate three classic experiments. The first finds quantitative agreement between levels of cooperation in a prisoner’s dilemma played online and in the physical laboratory. The second shows—consistent with behavior in the traditional laboratory—that online subjects respond to priming by altering their choices. The third demonstrates that when an identical decision is framed differently, individuals reverse their choice, thus replicating a famed Tversky-Kahneman result. Then we conduct a field experiment showing that workers have upward-sloping labor supply curves. Finally, we analyze the challenges to online experiments, proposing methods to cope with the unique threats to validity in an online setting, and examining the conceptual issues surrounding the external validity of online results. We conclude by presenting our views on the potential role that online experiments can play within the social sciences, and then recommend software development priorities and best practices.     

Generalized assignment models: with an applicationto technology transfer

Summary.  We consider a generalized assignment model where the payoffs depend on the number of matchings that take place. We formulate a simple non-cooperative game and look for subgame perfect equilibrium of this model. Existence is established for a wide class of games. We also look at a refinement criterion which, for the standard assignment model, selects the -optimal outcome as the unique equilibrium. We then apply these concepts to a model of technology transfer between domestic and foreign firms. Received: June 24, 1994; revised version October 12, 1995     

Solving coordination failure with “all-or-none” group-level incentives

Coordinating activity among members is an important problem faced by organizations. When firms, or units within firms, are stuck in bad equilibria, managers may turn to the temporary use of simple incentives—flat punishments or rewards—in an attempt to transition the firm or unit to a more efficient equilibrium. We investigate the use of incentives in the context of the “minimum-effort,” or “weak-link,” coordination game. We allow groups to reach the inefficient equilibrium and then implement temporary, flat, “all-or-none” incentives to encourage coordination on more efficient equilibria. We vary whether incentives are positive (rewards) or negative (penalties), whether they have substantial or nominal monetary value, and whether they are targeted to a specific outcome (the efficient equilibrium) or untargeted (apply to more than one outcome). Overall, incentives of all kinds are effective at improving coordination while they are in place, but there is little long-term persistent benefit of incentives—once incentives are removed, groups tend to return to the inefficient outcome. We find some differences between different kinds of incentives. Finally, we contrast our results to other recent work demonstrating greater long-term effectiveness of temporary incentives.      

农户过度放牧行为产生原因分析--来自黑河流域肃南县的农户调查

我国草地资源位居世界第二位,但目前退化非常严重,已经成为牧区生态环境保护和经济发展的主要制约因素。导致草地退化的原因多种多样,自然因素是不可调控因素,并且在近50年内并非是导致草地大面积退化的主要因素,实际上,人为因素才是最为主要的因素,其中过度放牧是最主要因素之一。农户作为草地使用和经营行为的微观主体,其行为可直接或间接地响应所有管理行为和制度的最终效应。通过针对肃南县草地退化进行的农户问卷调查进行详细剖析,并结合有关统计资料,尝试从农户角度阐释过度放牧行为产生的内在机制,认为农户的支出需求增加、收入的增幅减缓与缺乏稳定的收入预期、收入渠道单一以及生态支付意愿不高是导致农户过度放牧行为产生的根本原因。     

Modeling Effort and Lobbying in a Heterogeneous Common Pool Resource Setting

Extraction from a common pool resource (CPR), such as a fishery, can lead to socially inefficient and undesirable outcomes as a result of appropriation problems. Through regulation of the CPR, users may achieve a more profitable and socially efficient outcome. Feeny et al. (Land Econ 72(2):187–205, 1996) delve into some of the assumptions made by traditional CPR models and how use of those assumptions provides an incomplete framework to guide fishery policy. In the theoretical models we develop, we relax two of those assumptions: CPR users are homogeneous and are unable to create, or influence, management of the resource. We note a case where regulation of the individual user can induce others to harvest more, and relate this to the slippage effect concept. Regarding resource sustainability, we document situations where incentives exist for CPR users to lobby for tighter regulations and thus increase profits by limiting the tragedy of the commons influence.     

Foundations for contest success functions

In the literature, the outcome of contests is either interpreted as win probabilities or as shares of the prize. With this in mind, we examine two approaches to contest success functions (CSFs). In the first, we analyze the implications of contestants’ incomplete information concerning the ‘type’ of the contest administrator. While in the case of two contestants this approach can rationalize prominent CSFs, we show that it runs into difficulties when there are more agents. Our second approach interprets CSFs as sharing rules and establishes a connection to bargaining and claims problems which is independent of the number of contestants. Both approaches provide foundations for popular CSFs and guidelines for the definition of new ones.

“The strategic approach also seeks to combine axiomatic cooperative solutions and non-cooperative solutions. Roger Myerson recently named this task the ‘Nash program’.”(Rubinstein 1985, p. 1151)

     

Fiscal and monetary interactions when wage-setters are large: is there a role for corporatist policies?

This paper studies the macroeconomic consequences of alternative policy regimes in a closed economy where a central bank, a fiscal authority and a monopoly union interact via their effects on output and inflation. The analysis compares macroeconomic outcomes in a non-cooperative setting, where players may move sequentially or simultaneously, and in a regime of cooperation between the government and wage-setters. The cooperative regime captures a climate of accord among social parties that is finalised at common macroeconomic targets in the tradition of corporatism, as in the recent experience of “social pacts” in many European countries. The paper makes two main contributions. First, it shows that macroeconomic outcomes are suboptimal in the non-cooperative regime and may deliver extreme (undesirable) results even when all players share common ideal targets for output and inflation. All players would be better off with a less extreme value for output or inflation, yet they fail to reach a more advantageous allocation as long as there is an inherent conflict among their further objectives. Moreover, the result is robust to a change in the degree of central bank’s conservatism. Second, I find that cooperation between the government and the monopoly union towards common ideal targets for inflation, output and taxes enhances social welfare even in the absence of explicit coordination with the central bank.     

Misperceiving the value of information in predicting the performance of others

Economic models typically allow for “free disposal” or “reversibility” of information, which implies non-negative value. Building on previous research on the “curse of knowledge” we explore situations where this might not be so. In three experiments, we document situations in which participants place positive value on information in attempting to predict the performance of uninformed others, even when acquiring that information diminishes their earnings. In the first experiment, a majority of participants choose to hire informed—rather than uninformed—agents, leading to lower earnings. In the second experiment, a significant number of participants pay for information—the solution to a puzzle—that hurts their ability to predict how many others will solve the puzzle. In the third experiment, we find that the effect is reduced with experience and feedback on the actual performance to be predicted. We discuss implications of our results for the role of information and informed decision making in economic situations. Electronic Supplementary Material Supplementary material is available in the online version of this article at http://dx.doi.org/10.1007/s10683-006-9128-y. JEL Classification C91, D83     

Rationality,constitutions, and the ethics of rules

It seems clear that individuals stand to mutually benefit, in a wide variety of situations, from structuring their interactions in terms of constitutional practices. But a commitment to treat the rules defining such practices as setting real constraints on choice—a commitment to what could be characterized as an “ethics of rules”—is hard to reconcile with the standard, consequentialist theory of rational choice, which requires, in effect, that individuals regard any rule as providing no more than a “maxim” for choice. Such a theory of rational choice, then, constrains individuals to settle for a second best outcome in which choice is aligned with practice rules by means of strategies of precommitment and threats. The outcome is second best because such methods yield only partial alignment, and involve the expenditure of scarce resources, as well as a sacrifice of flexibility and freedom. To say this, however, is to identify the corresponding theory of rational choice as havingconsequentially unacceptable implications. A modified theory of choice is presented, which is still consequentially oriented, but which assesses consequences in a more holistic manner. It is then argued that this modified theory can provide a rational choice grounding for the needed “ethics of rules.” The author would like to thank three anonymous referees for their very helpful comments and suggestions.     

农户畜禽防疫服务支付意愿及其影响因素分析

基于对江苏、江西、内蒙、云南四省(区)447户的农户畜禽防疫服务调查,运用支付意愿方法,得到上述地区农户的畜禽防疫服务支付意愿,并通过Logistic回归模型对农户畜禽防疫服务支付意愿的影响因素进行了分析。研究结果表明,影响农户畜禽防疫服务支付意愿的因素除了农户家庭和生产等一些常见的特征变量外,还有农户所在社区畜禽防疫服务可及性等多方面的因素。基于这些实证研究结果,本文提出政府应增加投入,以及完善农村公共服务基础设施建设等相关政策建议。     

Networks of common property resources

A tragedy of commons appears when the users of a common resource have incentives to exploit it more than the socially efficient level. We analyze the situation when the tragedy of commons is embedded in a network of users and sources. Users play a game of extractions, where they decide how much resource to draw from each source they are connected to. We show that the network structure matters. The exploitation at each source depends on the centrality of the links connecting the source to the users. The equilibrium is unique and we provide a formula which expresses the quantities at an equilibrium as a function of a network centrality measure. Next we characterize the efficient levels of extractions by users and outflows from sources. We provide a graph decomposition which divides the network into regions according to the availability of sources. Then the efficiency problem can be solved region by region.     

The Green Solow model

We argue that a key empirical finding in environmental economics—the Environmental Kuznets Curve (EKC)—and the core model of modern macroeconomics—the Solow model—are intimately related. Once we amend the Solow model to incorporate technological progress in abatement, the EKC is a necessary by product of convergence to a sustainable growth path. We explain why current methods for estimating an EKC are likely to fail; provide an alternative empirical method directly tied to our theory; and estimate our model on carbon emissions from 173 countries over the 1960–1998 period.