全球化與都市結構

Abstract

全球化與資訊科技的發展，抹平了區域間的疆界，經濟活動越來越分散。城市的集中性與密集性沒有減少，大城市的規模愈來愈大，成長的速度沒有因為資訊科技的進步而減緩。Henderson andWang（2007）發現世界城市大小的分佈，沒有明顯的改變，少數大都市的規模越來越大。大都市趨向更多樣化（如紐約和東京）（Fujita and Tabuchi 1997），而一般都市有專業化的趨勢（Henderson 1997）。 Paul Krugman（1991）以Dixit and Sttiglitz（1977）獨占性競爭模型為基礎，考慮了產業的規模報酬遞增特性，提出一般均衡的分析架構，探討廠商聚集與區位選擇，稱之為新經濟地理（New economic geography），基本架構為核心－邊陲模型（core-periphery model）。新經濟地理成為近年來分析空間經濟的主要理論架構。Fujita and Thisse （2006）與Fujita and Gokan（2005）以新經濟地理架構為基礎，區分運輸成本與通訊成本，解釋工廠與總部的分離，與生產分散化的現象。另外，Duranton and Puga（2005）以非新經濟地理的模型，分析都市結構轉化為功能專業化(Functional specialization)的趨勢。產品品質與服務流程的創新，是近年來廠商創造附加價值的主要來源。經濟活動全球化、科技化，廠商的規模越大。大規模的營運總部，需要多樣化的人才與資源，以刺激知識與服務的創新。相關的研究，沒有考慮產業特性的轉變，對外部經濟性質的影響；另外應用NEG 模型的研究，很少延伸為多區域的架構進行模擬分析。本研究計畫的目的，是應用Krugman（1991）提出的獨占性競爭的理論基礎，分析全球化與資訊科技進步對廠商區位的影響，解釋全球化與都市結構轉變的關係。以新經濟地理的理論為基礎，延續Fujita and Thisse (2006)的模型，加入不同特質的聚集經濟變數，延伸為多個區域的分析架構，分析科技進步對產業分佈與都市結構的影響，模擬分析其特性，提供政策涵義。

Globalization and technological progress in transport and telecommunication technologies have lead to spatial fragmentation of production which is one of the main ingredients of the economic process of globalization. The decrease of impediment to trade in space has made firms’ location choice much more flexible. However, the agglomeration features are not diminishing due to the improvement of technology and globalization. Cities, especially some mega-cites even play more crucial roles in the worldwide economics activities. Why doesn’t the technological progress deteriorate the role of cities? Henderson andWang (2007) used a worldwide data set on all metro areas to examine the features of urbanization and city growth from 1960 to 2000. They found that technology improvement help bigger cities relative to smaller ones.Whereas increasing democratization helps smaller cities. Given these opposing effects, the overall relative size distribution of cities worldwide is unchanged over the time period. There are 11 mega-cities with population at least 12m accounting for 9.6% of the population of cities in 2000. However, there is only one mega-city over 12m accounting for 2.3% of the total population in 1960. The new economic geography (NEG) initiated by Paul Krugman (1991) uses general equilibrium framework to explain the formation of various forms of economic agglomeration in geographical space. The original NEG models adopted the monopolistic competition model from Dixit and Stiglitz (1977) has grown into one of the major branches of spatial economics. The introductory framework of NEG is the core-periphery model. It illustrates how the interactions among increasing returns at the level of the firm, transport costs and factor mobility can cause spatial economic structure to merge and change. The model assumes two regions with two production sectors, and firms are spatially integrated. Fujita and Thisse (2006) proposed a general equilibrium model of monopolistic competition with two countries based on NEG to explain the tendency of spatial fragmentation of production. They distinguished two different types of impediment of distance, i.e., transport costs for goods, and communication costs for doing business over space. This work suggests that a decrease in the trade costs of goods and the decline of communication costs between HQs and plants within firms may eventually cause the re-location of plants into the periphery. Fujita and Gokan (2005) further extended the model of Fujita and Thisse (2006) by assuming the possibility of multiple plants in one firm. This work shows that decreasing communication costs may cause firms concentrating their plants in low wage countries; whereas firms producing high trade-costs tend to have multiple plants serving to segmented markets. Duranton and Puga (2005) proposed a non-NEG formulation to explain the segmented market with multiple plants. It shows remarked evidences of the transformation of urban structure from sectoral to functional specialization. They found that a fall in the costs of remote management leads to a transformation of the equilibrium urban and industrial structure: headquarters clustered in larger cities, and plants clustered in smaller cities. Technological progress in transport and telecommunication technologies leads to the emergence of separate business centres and manufacturing cities.With greater benefits from proximity for headquarters and business services than for manufacturing, the shift from sectoral to functional specialization also implies that business centres are few and large whereas manufacturing centres are more numerous and smaller in size. The objective of this study is to propose an analytically framework based on the new economic geography to access the impact of technology progress and globalization on the equilibrium urban and industrial structure. Recent works by Duranton and Puga (2005), Fujita and Thisse (2006) and Fujita and Gokan (2005) have applied both the NEG and non-NEG frameworks to explain the spatial fragmentation of production. However, there is lack of analytically explanation for the counter-intuition tendency of few and large mega-cites. The proposed model will be adopted from the general equilibrium model in Fujita and Thisse (2006), the features of agglomeration economies will be introduced and distinguished into traditional and knowledge-based. Furthermore, we plan to extend the original two regions model to a multiple regions numerically computable model. Simulations will be applied to investigate the features of the proposed model.