技术外溢、策略性选址与产业集聚

大型寡头企业的策略性选址对形成地方性产业集聚、带动当地经济发展举足轻重.影响企业选址的因素很多,技术溢出和运输成本是其中的重要因素.文章建立了一个同时考虑技术溢出、运输成本和市场竞争的企业选址与产量竞争模型.研究发现企业集聚是完美纳什均衡,技术溢出是导致企业集聚的重要原因;企业集聚既可能发生在运输成本最低的地区,也可能发生在城市的其他区位,前提是企业在该区位集聚满足"技术溢出效应"大于"运输成本效应";企业在运输成本最低点集聚的均衡产量最大且企业利润最多,而在城市端点集聚的均衡产量最小且企业利润最小.     

总部集聚与工厂选址

总部经济的地理特征就是总部集聚。本文建立了一个全新的空间经济学模型,深入阐释总部与工厂分离的机制。模型分企业总部集聚和企业总部在南北地区均匀分布的两种情形,细致地探讨了跨地区运输成本、企业总部和工厂之间的交流成本以及地区间税收政策差异这三个因素相互影响、共同作用于工厂选址的机理。在其他条件不变的情况下,运输成本的降低将导致企业倾向于在总部集聚地区设立工厂;而无论运输成本高低,只要交流成本和外围地区劳动力工资上涨,更多的企业趋向于在总部集聚地区设厂;只有当外围地区的劳动工资降低或税率降低,更多的企业才趋向于在外围地区设厂。本文也再次验证了税收竞争的南部有利性与整体"竞次"(race to bottom)局面:一个地区的税收优惠政策不仅会对当地的企业产生影响,更会对总部集聚地区的其他企业利润产生负面影响。     

生产性服务业与下游企业的集聚研究:以广州市银行业为例

随着城市之间贸易的深入发展,现阶段中国城市化的一个重要特征就是生产性服务业向各城市群中心城市的集聚日益增长。本文以广州市四大国有商业银行为例,对生产性服务业与下游制造业的集聚进行了理论建模和实证分析。其结论认为:在理论上控制生产性服务业与下游制造业集聚的参数主要有中间服务与最终产品的运输成本和二者的边际产品以及中间服务的供应价格等;由于现阶段中国的生产性服务在城市之间的贸易程度尚较低,因此它们和制造业中的中间产品及最终产品生产企业既有集聚式分布又存在分散式布局模式,现代中国大都市的生产性服务业与下游企业的区位主要以集聚式布局为主要特征。     

传递成本、空间非一体化与城市经济结构转变

将东部100个城市分为三个层级,分别测算各层级城市2003—2008年生产性服务业相对于制造业的集聚程度,发现生产性服务业逐渐向少数核心城市集聚,而制造业向外围城市扩散。基于Duranton-Puga模型对这一现象进行研究,结果表明:当总部服务的传递成本或生产部门运输成本较高时,厂商选择空间一体化;反之,当总部服务传递成本较低并且生产部门运输成本也较低时,厂商选择空间非一体化;大量厂商生产组织方式的选择进一步影响城市的就业格局及经济结构,不同类型城市经济表现出按功能集聚的特征。     

集聚与分散：新经济地理学模型与城市内部空间结构、外部规模经济效应的整合研究

本文将城市内部空间结构和外部规模经济效应同时整合到标准的新经济地理学模型框架之中。模型的结论显示，作为重要分散力量的城市内部通勤成本和作为重要集聚力量的马歇尔外部规模经济效应都对经济活动的集聚程度有重要的影响，引入这两个因素使得模型更加接近经济现实。此外，模型的数值模拟结果显示，在引入外部规模经济效应后，即使运输成本为零，经济活动完全集聚在某一地区也可能是稳定均衡；同时，城市内部通勤成本确实会降低经济活动的集聚程度。     

成渝经济区城际轨道交通网空间布局合理性分析——基于空间经济学原理

根据中心地理论及空间经济学的基本原理,首先通过引入冰山运输成本建立了一个以重庆、川南、川东北、成都平原四个城市圈为支撑点的空间菱形经济模型,然后分析了不同的运输成本对产业集聚的影响,最后将成渝经济区城际轨道交通网的空间布局与城市圈的空间菱形模型相结合,阐释了城际轨道交通网规划的合理性。结果表明,城际轨道交通网的空间布局可降低各城市圈之间的运输成本,从而促进经济区内专业化分工和产业集聚、加快成渝城市群一体化进程。     

基于知识溢出效应的企业选址决策分析

本文研究基于知识溢出效应的企业选址问题.随着知识时代的来临,企业对区位因素的关注点从过去追求廉价的土地和劳动力等有形的生产要素转为对无形资源,特别是各种知识资源和创新条件的关注,知识溢出这个新的区位因子正逐渐构成企业空间竞争的新变量,成为企业选址的关键因素之一.以Hotelling模型为基础,引入知识溢出系数建立了企业选址与定价的两阶段博弈模型,分析了知识溢出和运输成本两个因素对企业选址的影响.经过对均衡解的分析,发现知识溢出对企业选址具有向心力,运输成本对企业选址具有离心力,两者的均衡决定了企业选址在集群中心还是选址在外围.     

我国制造业区域集聚程度决定因素的研究

本文分析了中国近年来（1998-2003）制造业行业集聚的趋势以及影响行业集聚的微观基础。研究表明样本期间中国制造业行业集聚呈上升态势。我们利用面板数据和动态估计过程模型，一定程度上控制了现有实证研究文献中存在的一些可能造成结果偏差的缺陷。我们发现：地方保护主义在很大程度上限制了中国制造业的区域集聚。同时，溢出效应、运输成本和自然禀赋也是影响行业集聚的重要因素。     

集聚与分散:新经济地理学模型与城市内部空间结构、外部规模经济效应的整合研究

本文将城市内部空间结构和外部规模经济效应同时整合到标准的新经济地理学模型框架之中。模型的结论显示,作为重要分散力量的城市内部通勤成本和作为重要集聚力量的马歇尔外部规模经济效应都对经济活动的集聚程度有重要的影响,引入这两个因素使得模型更加接近经济现实。此外,模型的数值模拟结果显示,在引入外部规模经济效应后,即使运输成本为零,经济活动完全集聚在某一地区也可能是稳定均衡;同时,城市内部通勤成本确实会降低经济活动的集聚程度。     

学习效应、拥挤性、地区的分工和集聚

为了解释经济发展、地区分工和产业集聚这一共生现象，本文设计了一个引入运输成本、专业化经济、学习效应和拥挤性的两地区两产品模型。模型显示了生产一消费一般均衡从地区之间没有分工到完全专业化的演进过程。通常，在上面提到的两个稳定均衡之间，还存在一个非稳定的内点均衡。一旦经济从上一个稳定均衡跳到并偏离带有临界规模专业生产人数的非稳定均衡，生产系统就进入了一个持续的转移动态过程，直到下一个稳定均衡。     

偏好、技术与工业化

Krugman(1 991b)的两地区模型解释了报酬递增的制造业企业为实现规模经济和降低运输成本而定位于需求较大的市场区域。本文通过引入部门间人口流动成本和地区间技术差异 ,认为新兴制造业可以在外围地区形成 ,并缩小地区间差异。     

2012年度"浦山世界经济学优秀论文奖"评选公告

中国世界经济学会2012年度浦山世界经济学优秀论文奖(简称浦山奖)评选活动已启动.浦山奖是中国世界经济研究领域的最高奖项,2011年,被国家教育部列为与孙冶方经济科学奖等奖项同等重要的优秀学术成果奖.     

Self-organized agglomerations and transport costs

This paper investigates the impact of the shape of transport costs on the structure of spatial equilibria. We consider a racetrack economic model in which firms and workers freely locate on the continuous space of a circumference. We present “reasonably” weak conditions on the shape of transport costs under which continuous distributions of firms and workers are never stable equilibria. We also characterize conditions on the shape of transport costs under which discrete distributions are stable equilibria. The results confirm the idea that agglomeration of firms and workers in few cities is a natural outcome of economic interactions.     

Interconnected communications networks and home market effects

Abstract.  This study develops a model of trade that highlights the effects of the interconnection of country‐specific communications networks as a driving force behind trade in high‐tech products with positive transport costs. By constructing a two‐country model of monopolistic competition with two production factors, it is shown that the locational decisions of firms may magnify the influence of interconnected networks. In a reversal of the standard home market effects, the abundance of unskilled labour in the developing countries can attract high‐tech firms from the developed countries. JEL classification: D43, F12, L13     

National Border Effects: Location, Not Nationality, Matters

A recent literature documents the downward impact of national borders on trade. This paper probes the relative importance of two potential sources of border effects: (1) pure locational factors, such as transport costs and tariffs; and (2) an inherent disadvantage for a firm selling in a foreign market. I am able to make this decomposition by using data on the local sales of foreign affiliates of US multinational enterprises, on US bilateral exports, and on domestic sales by host‐country firms. The “border effect” arises almost entirely from locational factors. If a firm establishes and sells from a subsidiary located in the foreign country, its local sales are about on a par with those of domestic firms in that market.     

Plant location and strategic environmental policy with inter-sectoral linkages

In recent debates on trade liberalisation the concern has often been expressed that with more competitive international trade governments will be worried that by setting tougher environmental policies than their trading rivals they will put domestic producers at a competitive disadvantage, and in the extreme case this could lead to firms relocating production in other countries. The response by governments to such concerns will be to weaken environmental policies (‘eco-dumping’). In competitive markets such concerns are ill founded, but there is a small amount of literature which has analysed whether governments will indeed have incentives for eco-dumping in the more relevant case of markets where there are significant scale economies; even here there is no presumption that the outcome will involve eco-dumping.In this paper we extend the analysis of strategic environmental policy and plant location decisions by analysing the location decision of firms in different sectors which are linked through an input-output structure of intermediate production. The reason why we introduce inter-sectoral linkages between firms is that they introduce an additional factor, relative to those already analysed in the literature, in the plant location decision, which is the incentive for firms in different sectors to agglomerate in a single location. This has a number of important effects. First, there is now the possibility of multiple equilibria in location decisions of firms. Following from this there is the possibility of catastrophic effects where a small increase in an environmental tax can trigger the collapse of an industrial base in a country; however there is also the possibility that a country which raises its environmental tax could attract more firms to locate in that country, because of the way the tax affects incentives for agglomeration. Finally, and again related to the previous effects, there is the possibility of a hysteresis effect where raising an environmental tax in one country can cause firms to relocate to another country, but subsequently lowering that tax will not induce firms to relocate back into the original country.We consider a simple model with two countries, two industries, an upstream and a downstream sector, and two firms per industry. The analysis proceeds through a three-stage game: in the first stage the governments of the two countries set their environmental policies; in the second stage the firms in both industries choose how many plants to locate and where; in the third stage firms choose their output levels, with the demand for the upstream firms being determined endogenously by the production decisions of the downstream firms. We assume that there are no limits to production capacity, so that firms do not build more than one plant in any country. However, firms may build plants in different countries because of positive transport costs. Although the model appears very simple, it cannot be solved analytically, so all the conclusions must be drawn from numerical simulations.     

Growth and Agglomeration

This article presents a model in which growth and geographic agglomeration of economic activities are mutually self-reinforcing processes. Economic agglomeration in one region spurs growth because it reduces the cost of innovation in that region through a pecuniary externality due to transaction costs. Growth fosters agglomeration because, as the sector at the origin of innovation expands, new firms tend to locate close to this sector. Agglomeration implies that all innovation and most production activities take place in the core region. However, as new firms are continuously created in the core, some relocate their production to the periphery.     

The Location of Firms in Unionized Countries*

This paper develops a two‐country economic geography model with Cournot competition, where the labor markets are unionized so that trade unions bargain efficiently with each firm over wages and employment. Agglomeration forces are present due to wage premia obtained by the trade unions. It is shown that if the bargaining power of unions differs across countries then, as trade costs are reduced, the country with relatively weak unions gradually acquires all firms. However, for a range of trade costs, it is also a locally stable equilibrium for all firms to locate in the country with strong unions.     

On the efficiency of environmental instruments in a spatial economy

This paper develops an efficiency criterion to evaluate environmental policy instruments in a spatial economy. We call an environmental policy regime at the regional level efficient if it guarantees not only an efficient distribution of emission permits within a region, but also an efficient locational pattern of mobile firms across the regions of a federation. Using marketable pollution rights or emission taxes, efficiency in this broad sense can only be achieved if revenues of regional environmental agencies are not transferred to regional firms. Direct controls neither support an efficient allocation of emission rights within a region nor locational efficiency of firms.