Sustainable Development and Resilience in Ecosystems

Two new important developments in environmental and resource economics is presented—non convex dynamics of ecosystems and wealth as an indicator of sustainable development. Non convex dynamics imply existence of resilience, that is the robustness of systems to withstand exogenous perturbations. Resilience can be regarded as an insurance against flips of the system into different basins of stability. Sustainable development, according to the Bruntland report, is the provision of productive resources to future generations to make it possible for them to live as well as the present generation. Thus, the value of changes in productive assets is therefore an index of whether an economy is on a sustainable path or not. Resilience can be regarded as one such productive asset and the paper discusses how one can define the value of this asset.     

State competition in higher education: A race to the top,or a race to the bottom?

How does competition affect higher education? This paper explores this question for public and private universities. Theory indicates that competition can push higher education policy in one of two different directions. On the one hand, competition may increase spending. For states, this would occur if states treat higher education as developmental; for private universities this would occur if they view spending as a means to attract students and prestige. On the other hand, competition may decrease spending if states treat higher education spending as redistributive, and competition may decrease spending by private schools if lower spending enhances their ability to attract students with low tuition. To determine which of these perspectives is most valid, we examine higher education policy choices in the 1980s and 1990s. We find that states appear to act as if higher education funding is redistributive while private schools appear to compete more on the basis of tuition than spending. These results demonstrate the important effects competition and governance structure have on higher education.Received: August 2001, Accepted: May 2002, JEL Classification: I2, I22, H72, I3     

国有煤矿经营者激励机制的系统动力学仿真研究

应用系统动力学理论与仿真方法,研究国有煤矿激励机制与经营者安全生产管理之间的关系,分析了激励机制对经营者安全管理的影响。仿真结果表明,应用系统动力学理论与仿真方法,可以对影响国有煤矿经营者的激励机制进行分析,为国有煤矿经营者激励机制的科学建立提供新的思路。     

Accounting for breakout in Britain: The industrial revolution through a Malthusian lens

This paper introduces a simple dynamic model to examine the breakout from a Malthusian economy to a modern growth regime. It identifies several factors that determine the fastest rate at which the population can grow without engendering declining living standards. We then apply the framework to Britain and find a dramatic increase in sustainable population growth at the time of the Industrial Revolution, well before the beginning of modern levels of income growth. The main contributions to the British breakout were technological improvements and structural change away from agricultural production, while coal, capital, and trade played a minor role. In addition to solidifying the link between the Industrial Revolution and rising living standards, this research reconciles the gradualist and limited Crafts–Harley view of the Industrial Revolution with a dramatic and rapid change in Britain’s macroeconomic character.     

Unemployment dynamics in an OLG economy with public pensions

Pension benefits in old age establish a disincentive to save in youth, thereby yielding lower levels of capital stock and the wage rate. As a result, the trade union has an incentive to change the composition of its two targets: employment and the wage rate. This paper develops a model that includes employment effects of public pensions via capital accumulation and union wage setting. Within this framework, we consider how contribution rates to the pension system influence the level and time path of the unemployment rate. It is demonstrated that (1) a higher contribution rate results in a lower unemployment rate, and (2) the economy with a high (low) contribution rate experiences monotone convergence towards (oscillatory convergence towards or a period-2 cycle around) the steady state. The author would like to thank an anonymous referee, Kazutoshi Miyazawa, and seminar participants at Osaka University for their useful comments and suggestions, and Masako Ikefuji and Hiroaki Yamagami for their research assistance. Financial support from the Japan Society for the Promotion of Science (JSPS) through a Grant-in-Aid for Young Scientists (B) (No.17730131), the Asahi Glass Foundation, the Japan Economic Research Foundation and the 21st Century COE Program (Osaka University) is gratefully acknowledged. All remaining errors are mine.     

Modeling population dynamics and economic growth as competing species: An application to CO2 global emissions

Since the beginning of the last century the world is experiencing an important demographic transition, which will probably impact on economic growth. Many demographers and social scientists are trying to understand the key drivers of such transition as well as its profound implications. A correct understanding will help to predict other important trends of the world primary energy demand and the carbon emission to the atmosphere, which may be leading to an important climate change. This paper proposes a set of coupled differential equations to describe the changes of population, gross domestic product, primary energy consumption and carbon emissions, modeled as competing species as in Lotka-Volterra prey-predator relations. The predator-prey model is well known in the biological, ecological and environmental literature and has also been applied successfully in other fields. This model proposes a new and simple conceptual explanation of the interactions and feedbacks among the principal driving forces leading to the present transition. The estimated results for the temporal evolution of world population, gross domestic product, primary energy consumption and carbon emissions are calculated from year 1850 to year 2150. The calculated scenarios are in good agreement with common world data and projections for the next 100 years.     

Ecological Transfers in Non-Human Communities Parallel Economic Markets in a General Equilibrium Ecosystem Model

Synopsis: The oft-cited analogies between ecological and economic systems are exploited to develop a many-species model of population dynamics. In economies, markets are the fundamental institutions in which the interaction of demands and supplies determine the quantities and prices of goods. However, economic markets are not appropriate for ecological communities, because markets rely on voluntary exchange, whereas plants and animals engage in involuntary transfers of biomass. A properly defined counterpart to markets based on biomass transfers permits a general equilibrium model of predator/prey and competitive interactions in a many-species community. Functional response from optimal foraging and predation risk provide the demand and supply, respectively, in the biomass transfers. Energy per unit time is scarce and predators and prey make optimum choices with respect to functional response and risk avoidance based on required energy expenditures. The energy expenditures are similar to economic prices: they determine foraging strategies and are beyond the control of the predators and prey, yet they are determined by the aggregate choices of all predators and prey and by population densities. The energies acquired from foraging are used in a new way to construct difference equations that determine the population dynamics. This revised version was published online in July 2006 with corrections to the Cover Date.     

The Dynamics of Self-Esteem and Physical Self: Between Preservation and Adaptation

The aim of this study was to model and characterize the psychologicalprocesses that underlie the dynamics of global self-esteem and physicalself over time. Twice a day for 228 consecutive days, seven participantscompleted a short inventory (PSI-6, Ninot et al., 2001) measuring sixsubjective dimensions: global self-esteem, physical self-worth, physicalcondition, sport competence, physical strength, and attractive body.Each series was modeled by means of ARIMA procedures. The resultsshowed that a simple moving average model provided a satisfactoryaccount for the dynamics of all series. This model suggests that acombination of two opposite processes underlies the dynamics ofself-concept: preservation, which tends to restore the previousvalue after a disturbance, and adaptation, which tends to inflectthe series in the direction of the perturbation.     

产业集群与人才集群的互动关系初探——基于系统动力学的思想框架

首先综述了产业集群与人才集群的相关理论,重点分析产业集群与产业集聚以及人才集群的区别与联系;继而基于系统动力学理论,从产业集群促进人才集群和人才集群促进产业集聚两个角度研究两者的互动关系;最后从微观、中观、宏观三个层次阐述促进产业集群与人才集群两者互动的政策建议。     

基于系统动力学的广西区域物流与经济协调发展研究

为了探讨广西区域物流与广西社会经济协调发展情况,找出制约广西物流产业的主要问题,运用系统动力学的反馈分析方法,归纳总结了研究的基本要素,建立了广西区域物流与经济协调发展的系统动力学模型,结合1990～2009年相关数据协整分析结果,应用Vensim PLE软件进行了模拟仿真,并对不同的政策进行实验,结果表明,刺激需求、合理投资以及大力培育人才等政策配合实施,能够有效地推动广西物流业和社会经济的协调发展。