我国发展“绿色保险”的经济学分析

本文从经济学的角度阐述了在我国发展"绿色保险"不仅有利于环境外部不经济的内部化和分散风险补偿损失,而且有利于社会可持续发展目标的实现和拓宽我国保险业的发展空间。     

Determinants of Voter Support for a Five‐Year Ban on the Cultivation of Genetically Modified Crops in Switzerland

While much effort has been devoted to estimating market premiums for non‐genetically modified (GM) food, the results of such research are largely silent about the preferences for the public good aspects, or externalities, of GM food production. For public goods, the closest substitute of private consumption decisions is voting on referenda. In November 2005, 55.7% of 2 million Swiss voters approved a five‐year moratorium (ban) on the commercial cultivation of GM plants in Switzerland. The present study examines how individual voting decisions were determined by: (i) socioeconomic characteristics; (ii) political preference/ideology; and (iii) agreement with a series of arguments in favour and against the use of GM plants in Swiss agriculture. The analysis is based on the data of the regular voter survey undertaken after the national‐level voting in Switzerland. The results suggest that current concerns about the use of genetically engineered plants in agriculture may not automatically decrease with higher levels of education/knowledge and generational change. Furthermore, analysis of voter motives suggests that public support for a ban on GM crops may be even larger in other countries, where industrial interests in crop biotechnology are less pronounced.     

A Hotelling model with a ceiling on the stock of pollution

Environmental agreements such as the Kyoto Protocol aim to stabilize the amount of carbon in the atmosphere, which is mainly caused by the burning of nonrenewable resources such as coal. We characterize the solution to the textbook Hotelling model when there is a ceiling on the stock of emissions. We consider both increasing and decreasing demand for energy. We show that when the ceiling is binding, both the low-cost nonrenewable resource and the high-cost renewable resource may be used jointly. A key implication is that if energy demand were to decline in the long run, we may supplement energy supply through ‘clean’ renewables to meet the environmental standard, but then revert back to using only ‘dirty’ fossil fuels in the future when the ceiling has become non-binding. That is, the much heralded societal ‘transition’ to clean energy resources may be short-lived.     

Negative externalities and Sen’s liberalism theorem

Summary. Sen’s seminal, negative theorem about minimal liberalism has had a profound effect on economics, philosophy, and the social sciences. To address concerns raised by his result, we show how Sen’s assumptions must be modified to obtain positive conclusions; e.g., one resolution allows an agent to be decisive only if his choice does not impose “strong negative externalities” on others. We also uncover a significantly different interpretation of Sen’s societal cycles: rather than describing the rights of individuals to choose, the cycles identify when these choices impose difficulties on others. Other ways to address Sen’s difficulties come from game theory.Received: 14 October 2004, Revised: 7 March 2005, JEL Classification Numbers: D71, C70, D62.Donald G. Saari: Correspondenc toThe research of D. Saari was supported by NSF grant DMI-0233798. Our thanks to P. Hammond for suggesting some useful references. Some of our joint results were reported in Brunel (now Petron) (1998).     

Network topology and the efficiency of equilibrium

Different kinds of networks, such as transportation, communication, computer, and supply networks, are susceptible to similar kinds of inefficiencies. These arise when congestion externalities make the cost for each user depend on the other users' choice of routes. If each user chooses the least expensive (e.g., the fastest) route from the users' common point of origin to the common destination, the result may be Pareto inefficient in that an alternative choice of routes would reduce the costs for all users. Braess's paradox represents an extreme kind of inefficiency, in which the equilibrium costs may be reduced by raising the cost curves. As this paper shows, this paradox occurs in an (undirected) two-terminal network if and only if it is not series-parallel. More generally, Pareto inefficient equilibria occur in a network if and only if one of three simple networks is embedded in it.     

Heterogeneity vs. externalities in technological competition: A tale of possible technological landscapes

The article presents a stochastic interaction model based on Gibbs random fields to analyze technological competition in a population of heterogeneous adopters with local or global externalities. The relationships between both heterogeneity and externalities and imperfect and asymmetric information are first emphasized. When local externalities and heterogeneity coexist, the technological landscapes of the industry are then shown to depend on the relative influence of these two parameters, with a phase transition: technologies coexist either in approximately equal market shares when heterogeneity is high enough or with one of the technologies only surviving in technological niches when local externalities dominate. Niches do also spontaneously appear: technological options survive in economic space due to the existence of some amount of heterogeneity among agents. On the contrary, when global externalities are added, pure standardization almost always occurs. We finally argue that different public policies should be designed so as to fit with different technological landscapes.     

CONSUMPTION AND LEISURE EXTERNALITIES, ECONOMIC GROWTH AND EQUILIBRIUM EFFICIENCY

This paper analyzes the effects of consumption and leisure externalities on growth and welfare in a two‐sector endogenous growth model with human capital accumulation. Both types of externalities are shown to affect the long‐run equilibrium and optimal growth rates in a rather different way. The relationship between the steady state of the market and the centrally planned economy is also analyzed. The optimal growth path can be decentralized by resorting to consumption or labor income taxation, whereas capital income should be untaxed. Numerical simulations suggest that growth and welfare effects of mild consumption and leisure externalities may be quantitatively important.     

Case study of agri-environmental payments: The United Kingdom

The Environmentally Sensitive Areas (ESA) program, when launched in the United Kingdom (UK) in 1986, was the first agri-environmental program in the European Union (EU). This program grew to a total of 43 designated ESA schemes in the UK as a whole, 22 of which were in England. A variety of agri-environmental payments programs were created to supplement and complement the ESA schemes in years to follow. The most prominent of these in England was the Countryside Stewardship Scheme (CSS), established in 1991. The CSS was available to farmers outside the ESAs, and like the ESA program, was intended to protect valued landscapes and habitats and to improve public enjoyment of the countryside. By 2003, over 10% of England's agricultural land was enrolled in either ESA or CSS agreements. These voluntary agreements were long-term contracts (usually for 10 years) between the government and farmers to provide environmental services. Several major evaluations of the ESA program and the CSS were conducted over the years, and the results of many of those evaluations and the lessons derived are synthesized and summarized in this article. Both the ESA program and the CSS proved to be generally effective in enrolling many farmers in the entry-level contract tiers, thereby halting or slowing degradation of rural landscape and other environmental features. However, the schemes did not generally offer sufficient economic incentives to attract high levels of enrollment in the intensive farming areas. Also, the schemes were limited in their success in enrolling farmers in higher payment tiers, tiers that required more substantial changes in farming practices. The high crop and livestock-related payments received by farmers under the EU's Common Agricultural Policy (CAP) contributed to the disincentives to participate, especially in higher tiers. Following the latest (2003) reforms of the EU's CAP, England's ESA program and CSS are being replaced by a new, consolidated package of schemes that draws on lessons learned over the past 15-20 years with these two flagship programs.     

产业相关多样性对区域经济韧性的影响

随着全球化趋势的不断加强,地区面对的外部波动日益加剧,关于区域经济韧性的研究逐渐受到关注。地区产业结构布局特征关乎地区生产结构,以相关多样性为代表的布局特征日益受到重视,但是其对于区域经济韧性的影响却未有定论。以我国27个省市2005-2016年面板数据为样本,采用门槛模型,引入地区创新水平差异,研究产业相关多样性对区域经济韧性的具体影响。结果表明,相关多样性对区域经济韧性的影响因为地区整体创新水平差异而呈现出显著的区间效应：当地区创新水平较低时,相关多样性对区域经济韧性呈负向影响,且负向影响随创新水平的上升而逐渐减弱;当地区创新水平较高时,相关多样性对区域经济韧性呈显著正向影响。结合我国地区多样化与创新水平现状提出：在新时代背景下,加强相关多样性布局与地区创新水平建设是地区应对外部冲击的有效思路。     

Interregional Migration of Human Capital and Unemployment Dynamics: Evidence from Italian Provinces

Since the mid‐1990s interregional migration flows in Italy have dramatically increased, especially from the South to the North. These flows are characterized by a strong component of human capital, involving a large number of workers with secondary and tertiary education. Using longitudinal data for the period 2002–2011 at NUTS‐3 territorial level, we document that long‐distance (i.e., South‐North) net migration of high‐skill workers has increased the unemployment at origin and decreased it at destination, thus deepening North–South unemployment disparities. On the other hand, long‐distance net migration of low‐skill workers has had the opposite effect, by lowering the unemployment at origin and raising it at destination. Further evidence also suggests that the diverging effect of high‐skill migration dominates the converging effect of low‐skill migration. Thus, concerns for an ‘internal brain drain’ from Southern regions look not groundless.