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51.
52.
Economic models of urban spatial patterns have largely ignored complexity as an attribute of urban systems. Complexity theorists
on the other hand have not made sufficiently serious and sustained attempts to verify empirically the relevance of complex
systems models for urban spatial patterns. This research bridges this gap by simulating the evolution of an urban employment
pattern as a self-organizing complex system and seeking its empirical validation. It estimates the model’s parameters by using
firm data aggregated to the level of municipalities in Cleveland-Akron Consolidated Metropolitan Statistical Area in Ohio.
The interaction among four parameters, forces of attraction and dispersion and their respective rates of dissipation with
distance, are modeled as a two-dimensional complex system. The research compares the states of the modeled system with empirical
data to present viable methods for verification, calibration and validation of such models.
相似文献
53.
Song-ken Hsu 《The Annals of Regional Science》2006,40(3):531-544
One of main conclusions drawn by prior studies is that in a spatial market, the shape of the demand function can fully determine whether one simple pricing policy is superior to another either on the basis of the firm’s preference or social desirability while there is one assumption that is generally stipulated, namely, that the fixed market area assumption under which the market area is exogenously determined and remains the same under alternative pricing policies. In order to fully understand the impact of a demand function, this paper attempts to reexamine the relative economic advantages between two simple spatial pricing policies in a world with variable market area, that is, the market area is endogenously determined the price charged. We show that the fixed market area assumption is valid only where demand is linear, but no longer holds where demand is nonlinear. Moreover, and more importantly, we show that in a world with variable market area, some conclusions drawn by prior studies on the relative economic benefits of two pricing policies cannot remain valid. The main conclusion of this paper is that even the relative economic benefits of two simple spatial pricing policies is concerned, the impact of economic space is significant.
相似文献
Song-ken HsuEmail: |
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55.
Regional labor markets in Finland: Adjustment to total versus region-specific shocks 总被引:1,自引:0,他引:1
This article analyses regional labor market adjustment in the Finnish provinces during 1976–2000. We investigate the inter-relations
of employment, unemployment, labor force participation, and migration to see how a change in region-specific and total labor
demand is adjusted. The analysis reveals that region-specific labor demand shocks adjust mainly via participation, whereas
total shocks are adjusted by unemployment. The region-specific component of labor demand shock has shorter-lived effects on
unemployment and participation, but its effect on employment is permanent. Conversely, total shocks leave no permanent effect.
Migration is more important in the region-specific case where, after a few years, it acquires a large role in the adjustment
process. 相似文献
56.
Many things in the natural world consist of an ever-larger number of ever-smaller pieces. This is called a fractal, which implies both the power law and rank size rule. Various models have been applied to explain the power law or Zipfs law in the distribution of city size. Gibrats law proposes general and neat interpretations for this regularity in a city distribution, but the homogeneity assumption in Gibrats law shows a disregard of the agglomeration effect that is essential in economic interpretation. The purpose of this paper is to examine the relation between the feature of increasing returns in the dynamic growth process and the property of power law in the static limiting distribution. We apply the path-dependent processes in Authur (2000) called nonlinear Polya processes to analyze the relation between the feature of agglomeration in the path-dependent processes and rank-size relations in the limiting distributions. The simulation result shows that the growth process with a diminishing returns agglomeration economy or a bounded increasing returns agglomeration economy converges to a stable limiting distribution with a constant expected proportion. On the contrary, the growth process with an unbounded increasing returns agglomeration economy could generate a fractal kind of limiting distribution with a time variant expected value. The unbounded increasing returns agglomeration economy is the necessary condition to generate the rank size rule in the limiting distribution. Given the assumption of agglomeration economies and robust evidence of Zipfs in city distribution, our result suggests that agglomeration benefits increase without a ceiling as residents are added to the city. The increase of the diseconomies of agglomeration (congestion, pollution, crime, etc.) is not too severe to confine the limiting level of the net agglomeration effect.The author acknowledges the National Science Council for the financial support on the study (Project NSC 91–2415-H-004–016).Received: July 2002 / Accepted: March 2003 相似文献
57.
This paper extends the empirical literature on the effects of trade liberalization on regional disparities within a country. Studying the case of the Central and Eastern European countries, we find significant convergence of real wages in Poland and Bulgaria, only. Furthermore, countries with a faster growing export openness in the period 1991–1998 experienced larger increases in their regional disparities. Especially, intermediate goods trade seems to have been a main driving force. Our estimates suggest that the long run impact of rising intermediate goods export openness in the last decade was a 23% increase in the average economys variance of real wages.Received: December 2002/Accepted: January 2004The authors are grateful to two anonymous referees for their helpful suggestions. 相似文献
58.
餐饮业油烟污染扰民问题一直是近年来重庆市民投诉的热点。为确切了解目前重庆市油烟污染现状及市民对油烟污染问题的反映,为重庆市环保决策提供科学依据,调查了不同性别、不同年龄和不同居住环境的重庆市民对油烟污染和其他环境污染问题的认识以及重庆市民对油烟污染的投诉情况。结果表明,油烟污染是除大气污染和噪声污染以外影响重庆市民生活的最大的污染类型,不同性别、不同年龄和不同居住环境的人们对油烟污染影响的感受不同。最后分析探讨了重庆市油烟污染问题难以有效解决的原因,并提出了治理油烟污染的合理化建议。 相似文献
59.
Applying social network analysis in economic geography: framing some key analytic issues 总被引:5,自引:0,他引:5
Social network analysis attracts increasing attention in economic geography. We claim social network analysis is a promising
tool for empirically investigating the structure and evolution of inter-organizational interaction and knowledge flows within
and across regions. However, the potential of the application of network methodology to regional issues is far from exhausted.
The aim of our paper is twofold. The first objective is to shed light on the untapped potential of social network analysis
techniques in economic geography: we set out some theoretical challenges concerning the static and dynamic analysis of networks
in geography. Basically, we claim that network analysis has a huge potential to enrich the literature on clusters, regional
innovation systems and knowledge spillovers. The second objective is to describe how these challenges can be met through the
application of network analysis techniques, using primary (survey) and secondary (patent) data. We argue that the choice between
these two types of data has strong implications for the type of research questions that can be dealt with in economic geography,
such as the feasibility of dynamic network analysis. 相似文献
60.