Heterogeneous firms,trade liberalization and agglomeration

Abstract In this study, we develop an economic model to examine agglomeration of heterogeneous firms following trade liberalization. In a closed economy, we show that high‐productivity firms are more likely to agglomerate because they benefit more from agglomeration than their low‐productivity counterparts. However, trade liberalization, especially with a high‐productivity partner, favours partial agglomeration; that is, low‐productivity firms relocate away from the region where high‐productivity firms agglomerate. Consequently, the welfare gap between the domestic regions of an economy narrows following trade liberalization. The latter result suggests that trade liberalization promotes regional economic development.     

What will be the environmental effects of new free-floating car-sharing systems? The case of car2go in Ulm

The purpose of this paper is the discussion of the environmental effects of a free-floating car-sharing system operating in Ulm, Germany. The system, called car2go, allows users to take and leave vehicles at any point within the city limits. Thus opposed to traditional car-sharing, there are no fixed stations and in particular one-way trips of any length are possible without a booking requirement. Since this is the first free-floating system in operation, there is as yet no associated empirical research. Based on primary data from a survey, a model was developed to forecast the environmental impact of car2go. The prognosis considers the period of five years after the launch of car2go in 2009 and indicates a CO₂-reduction per average car2go-user. In addition, more than a quarter of the survey respondents stated that they may forgo a car purchase if car2go was offered permanently. By reaching a greater share of citizens than traditional systems, the results indicate that free-floating car-sharing systems could contribute to reducing private vehicle ownership in cities.     

安徽省R&D投入及其结构与经济增长关系的实证研究

利用1994—2008年安徽省R&D经费投入与GDP总量的数据,运用ADL模型并结合滞后效应的概念,对安徽省R&D经费投入与经济增长的关系进行了实证研究,以AIC信息准则、SC信息准则作为选择最优滞后阶数的判断标准,对R&D经费投入及经济增长两个变量的滞后期进行估计并测算。结果表明:安徽省R&D经费投入对经济增长的贡献是显著的,但R&D投入分配结构不合理,基础研究投入最少,而其对经济增长的边际贡献却最大,实验发展投入最多,而其对经济增长的边际贡献却最小,从而导致R&D投入分配效率低下,长期甚至可能无效率。     

美国R＆D投入情况分析

本文介绍并分析了美国近年全社会R＆D的投入情况,包括总量、结构和美国联邦政府R＆D投入情况,以及金融危机后政府在科技方面的投入趋势。研究并分析了美国科技预算管理体制及联邦政府科技行政部门在科技预算形成中的作用。美国R＆D预算管理具有多渠道、分散的特点。各个联邦部门科技预算的编制、审核和决策具有相对独立性。     

TOURISM AND INDUSTRIAL AGGLOMERATION

Tourism generates considerable income and employment in host countries and regions, which substantially improves local economies. Meanwhile, the manufacturing sector remains the most important part in regional and national economies. This paper investigates their interdependence through a general‐equilibrium analysis. On the one hand, a tourism boom is pro‐industrialization because the income generated by tourism attracts more manufacturing firms and, on the other hand, de‐industrialization for attracting labour from the manufacturing sector. We clarify conditions of trade balances in three sectors. The welfare analysis clarifies conditions for the smaller country to be better off, and conditions for the equilibrium to be optimal.     

研发团队有效性的层次物元评价模型及应用

鉴于团队有效性概念的模糊性和单项指标评价结果的不相容性,将层次分析法与物元法建模相结合,构建层次物元评价模型对团队有效性进行评价。应用该模型对中兴研发团队的有效性进行评价,综合评价结果与该团队实际情况相符,说明该模型有效、可行。层次物元评价模型为研发团队有效性评价提供了一条新的途径。     

质量随机的研发竞赛模型与最优奖励

假设研发质量具有随机性,建立了研发竞赛的非合作博弈模型,分别探讨了完全信息和不完全信息条件下竞赛参与人与竞赛发起者的最优策略。研究发现：竞赛参与人的研发投入水平在完全信息和不完全信息条件下都随自身研发效率的降低而降低;研发参与人的类型信息不完全程度越高,参与人的均衡研发投入越低;在每一种信息类型组合下都存在着最优奖励使得竞赛发起者的期望收益最大。     

矿业城市循环经济技术支撑体系研究

矿业城市是随着矿产资源的开发而形成和发展起来的,矿业城市为我国持续快速经济增长提供大量物质保障的同时,其自身的资源、环境及发展问题也更加突出。着眼于矿业城市的持续发展,论文分析了矿业城市资源、环境问题的技术选择导向,构建了矿业城市循环经济的＂5R＂原则及相应的技术支撑体系,并对该体系的具体内容及实现途径进行了探讨。研究认为：①从技术角度而言,资源、环境外部性导向和追求劳动生产率的技术选择,是矿业城市资源、环境和发展问题的主要原因;②基于资源产业运行中对区域资源、环境的强干扰特征,矿业城市循环经济系统应包含开源化、减量化、再使用、再循环、再恢复五个方面（＂5R）＂原则,产业提升过程中＂5R＂原则不断耦合与互动,实现矿业城市的持续发展;③围绕矿业城市循环经济系统的运行,应建立包括＂5R＂及产业提升六个方面的技术支撑体系;④技术支撑体系的实现,需要企业、产业链、生态园区、产业集群体、行业协会及矿业城市等不同层次在技术引进、技术创新、技术整合等方面的协调运行。     

Rethinking the area approach: Immigrants and the labor market in California

A framework that uses a Constant Elasticity of Substitution (CES) production function with skill differentiation and integrated national labor markets has predictions for the employment effect of immigrants at the local level. The employment (rather than wage) response to immigration by skill in a state reveals the production substitutability-complementarity between native and immigrant labor. This, in turn, reveals the degree to which immigrants stimulate or depress the demand for native labor. To estimate this elasticity, I use a novel instrument based on demographic characteristics of total Central American migrants or of the Mexican Population to predict immigration by skill level within California. Looking at immigration to California between 1960 and 2005 these estimates support the assumption of a nationally integrated labor market by skill and they support the hypothesis that natives and immigrants in the same education-experience group are not perfectly substitutable. This explains the counter-intuitive fact that there is a zero correlation between immigration and wage and employment outcomes of natives in the state.     

融资约束、代理成本与企业研发效率——基于中国工业上市公司的实证研究

本文以2004~2012年我国工业上市公司中已披露研发费用的企业为样本,采用随机前沿分析方法研究融资约束和代理成本对企业研发效率的影响,主要得出以下结论:融资约束对企业研发效率有显著的正向影响;而代理成本与企业研发效率之间呈现出显著的负向关系;企业的融资约束可以缓解代理成本对企业研发效率的负向作用。此外,本文的实证结果还表明,国有控股企业的研发效率低于非国有控股企业的研发效率,而且企业研发并没有随着研发强度的提高而产生规模效应。