关键词: 递增收益；城市增长；经济活动密度；中间产品；珠三角；香港

Abstract:

Most economic activities occur in cities. A city, as a regional pole of growth, drives the whole regional economics to develop. There is such a situation especially in the region of Zhujiang Delta in the medium-term of industrialization. But what is the cause of urban growth? In this paper we utilize the framework of new economic growth and new economic geography and try   to study the effects of increasing scale return of the density of economic activity. The paper starts by discussing the related literature and points out that there are some puzzled things at the studies about sources of urban scale’s growth in the economic theoretical circles. In Section 2, we analyze three models about the relation of city size of population and urban growth and the relation of the density of economic activity and urban growth under different hypotheses. In Section 3, we utilize the data of the region of Zhujiang Delta and Hong Kong to make regression analysis and comparison analysis. The main result is summarized in Section 4, that is: from the perspective of the external-economic approach, the monopolistic competition approach or the human capital approach under the premise of external-economy, the spatial density of economic activity is the result of agglomeration on one hand and on the other hand it can also promote the returns of scale economics and accelerate urban growth. So the density of economic activity can become the main endogenous source of aggregate increasing returns in the certain increasing range to promote urban growth.This paper both gives a theoretical basis for August Losch’s way to determine the location of city system in market density and shows a very effective path to drive the regional economic integration through the point-axle economic system for regional economic development.

Key words: Delta；Hong Kong, density of economic activity, increasing returns, intermediate products；Zhujiang , urban growth