City Size,Commuting Cost and Household Savings Rate:Evidence from China

Economics literature has long overlooked an important economic phenomenon:Residents in large cities tend to save a smaller percentage of their disposable income than their peers in small and medium-sized cities.As an explanation for this phenomenon,this paper puts forth the hypothesis that:Residents in large cities purchase more services to increase their leisure time,which is reduced by longer commuting time than in small and medium-sized cities,thus lowering their household savings rate.We conducted an empirical study using panel data of China’s prefecture-level cities and urban household survey data,and employed an instrumental variable to address the endogeneity problem.The result confirmed the accuracy of the above hypothesis.In identifying the economic phenomenon and putting forth the hypothesis,this paper(i)creates a theoretical link between city size and household savings rate,which helps unravel the determinants of the urban household savings rate;(2)provides important implications for China’s policy-making on domestic consumption,urban populations,and industrial development.Priority should be given to developing large and medium-sized cities given the positive effects on domestic consumption and service sector development,and migrant labor shall not be barred from entering large and medium-sized cities to provide services to local residents.

Gini Index for Cities: A Preliminary Study on Regional Differences of Chinese City Size Distribution

City size distribution is of interest because of a number of key stylized facts, including notably Zipf's law for cities and the importance of urban primacy. But a new and more efficient method Gini index can be used for calculating regional city size distribution. This paper begins by developing a calculation method for the Gini index, dividing the whole country into 26 areas and then calculating each area's Gini index value. Based on these calculation results, this paper gives a preliminary study on regional differences of its city size distribution and the dynamics.

Dialect Diversity,Factor Agglomeration and City Size:Empirical Test Based on Satellite Night-Time Light Data

Since the reform and opening up program was initiated in 1978,China’s urbanization has made rapid progress,but urban development remains unbalanced and insufficient.From the perspective of social and cultural diversity,this paper explores the impact of dialect diversity on city size.Dialect diversity impedes the expansion of cities by causing a trust segmentation and impeding cross-regional factor flow and the factor agglomeration effect.Based on the regional dialect diversity indicator and the NPP-VIIRS city night-time light index of 2016,this paper offers an empirical study of the impact of dialect diversity on city size.Econometric results indicate that dialect diversity has a significantly negative impact on city size.On average,an increase of each dialect sub-category leads to a decrease in city size estimated by the night-time light index by 4.55%.Robustness test and causality identification reveal that the estimated results of this paper have a robust causal relationship.Further empirical research indicates that dialect diversity affects the expansion of city size by inhibiting the flow and agglomeration of labor,capital and technology factors.Our research suggests that the development of diverse and inclusive modern cities needs to balance the costs and benefits of cultural diversity and uniformity,break through cultural barriers,remove cultural prejudices,raise the level of social trust,and give play to the complementary effect of cultural diversity.

Optimal City Size in China:An Extended Empirical Study from the Perspective of Energy Consumption

The optimal city size has always been a heated topic for debate in China. Given the background of global warming and fossil fuel crisis, it is argued that the issue should be considered from not only the perspective of economic benefits of a city but should also consider the energy consumption efficiency of the city. On the basis of the energy consumption data of 286 cities at the prefectural level and above in Chinese mainland except Lasa, which are obtained from the EU Emission Database for Global Atmospheric Research(EDGAR), this paper carries out an empirical analysis on the relationship between the city size and the energy consumption efficiency of the city. Then based on this analysis, the paper further examines the economic benefits, social benefits, and environment quality of cities in different scales, and the findings reveal that large cities with 2 – 5 million population have the highest efficiency in all these aspects.

Chinese City Size Ranking: A Comparative Study of the Urban Built-Up Area Based on Remote Sensing Data

Without a clear and unified definition of the urban built-up area, many city rankings by area are inconsistent, giving rise to confusion among the general public and even scholars. This paper summarizes various definitions of the urban built-up area and proposes three definition methods: all urban built-up areas in a municipal administrative area, concentrated contiguous built-up areas, and urban built-up areas in central cities. From the latest Landsat 8 satellite images, the paper obtains the data of urban built-up area in some of China’s big cities and makes a comparative study between the results of the urban built-up areas by the three definition methods and three other common statistical data. It finds that neither the area data nor the ranking is consistent. Finally, it further explores what causes differences in rankings and gives some advice for improving the definition of the urban built-up area.

Structural and robustness properties of smart-city transportation networks

The concept of smart city gives an excellent resolution to construct and develop modern cities, and also demands infrastructure construction. How to build a safe, stable, and highly efficient public transportation system becomes an important topic in the process of city construction. In this work, we study the structural and robustness properties of transportation networks and their sub-networks. We introduce a complementary network model to study the relevance and complementarity between bus network and subway network. Our numerical results show that the mutual supplement of networks can improve the network robustness. This conclusion provides a theoretical basis for the construction of public traffic networks, and it also supports reasonable operation of managing smart cities.

Sequential city growth： Theory and evidence from the US

City growth patterns are attracting more attention in urban geography studies. This paper examines how cities develop and grow in the upper tail of size distribution in a large-scale economy based on a theoretical model under new economic geography framework and the empirical evidence from the US. The results show that cities grow in a sequential pattern. Cities with the best economic conditions are the first to grow fastest until they reach a critical size, then their growth rates slow down and the smaller cities farther down in the urban hierarchy become the fastest-growing ones in sequence. This paper also reveals three related features of urban system. First, the city size distribution evolves from low-level balanced to primate and finally high-level balanced pattern in an inverted U-shaped path. Second, there exist persistent discontinuities, or gaps, between city size classes. Third, city size in the upper tail exhibits conditional convergence characteristics. This paper could not only contribute to enhancing the understanding of urbanization process and city size distribution dynamics, but also be widely used in making effective policies and scientific urban planning.

Administrative Hierarchy,Government Favoritism and Size Growth of Cities

Based on the significant difference of China’s cities at different(administrative)hierarchical levels in population growth over the past three decades,this study explains the influence of urban development policies(industrial policies and land policies)on the gap in urban population growth from the perspective of government favoritism.Taking 423 cities during 1990-2015 as samples,this paper selects two indicators,setting up national development zones and turning counties into districts,to represent government favoritism and applies the PSM-DID method.The empirical result shows government favoritism in setting up national development zones and turning counties into districts is conducive to urban population growth and helps generate synergy effects of industrial and land policies.Market potential of cities is an important condition for the effect of government favoritism.The result fi nds that government favors higher-level cities and coastal ones,but overlooks inland medium-and low-level cities,resulting in the shallow U-shaped characteristics of“higher on both ends and lower in the middle”in population growth of cities at different levels.In order to prevent inland medium-and low-level cities from“collapsing”relatively,the government should break its favoritism for high-level cities,transform industrial and land policies from“preference system”to“generalized system of preference”,and put greater favor of inland medium-and low-level cities with certain market potential.

Aerosol size distributions during haze episodes in winter in Jinan, China

Number concentrations and distributions of 10-10,000 nm particles in a large city （Jinan） in the North China Plain were measured in winter 2009. The mean number concentrations of nucleation mode （10-20 nm）, Aitken mode （20-100 nm）, and accumulation mode （100-1000 nm） particles, as well as total particles were 925, 6898, 2476, and 10,299cm-3, respectively. Two severe haze episodes, with elevated concentrations caused by pollutants accumulating, were observed. Accumulation mode particle concen- trations were significantly higher during the episodes than on clear days, and nucleation mode particle concentrations were pronouncedly higher on clear days than during the episodes. The peaks of domi- nant number, surface area, and mass size distributions were around 30-50, 200-300, and 200-400 rim, respectively, both during the haze episodes and on clear days, but elevated mass and surface area con- centrations around 500-600 nm were also observed during the haze episodes, suggesting these particles had significant contributions to haze formation. These particles were probably formed through larger droplets in cloud and fog evaporating. Two new particle formation events, probably triggered by strong photochemical processes on clear days and significant traffic emissions during haze episode 2, were found. Significant insights were made into haze formation in a oolluted Chinese urban area.

Relations Between the Industrial Output and the Size of Cities in China

Currently, there are controversies onthe development policy for large, mediumand small sized cities. To appraise the ad-vantages and disadvantages of cities of vari-ous sizes from different angles, conclusionscan vary tremendously. Starting from devel-opment productivity, cities in China shouldaim at achieving good output returns. This article tries to discuss the outputreturns of cities of different size from

基于网络招聘大数据的中国城市规模与就业增长关系研究

This article explored China’s urban employment dynamics with particular focus on the city size effect.Big data derived from the largest recruitment website were used to examine the direct and indirect impacts of city size on employment demand by using mediating and moderating models.We also investigated the roles of the government and location factors which have seldom been considered in literature.Results showed that the concentration degree of new jobs is higher than that of stock employment and population across cities,implying a path dependency mechanism of job creation and employment expansion.Meanwhile,numerous job posts in inland central cities are probably a symptom of more even distribution of employment in future China.Econometric models further verified the significant correlation between city size and job creation.Moreover,industrial diversity,fixed asset investment,and spatial location have heterogeneous effects on employment demand in cities of different sizes and different levels of administration.These results can not only deepen our understanding of the crucial role of city size in urban employment growth but also demonstrate the future trend of labor and population geography of China.Policy implications are then proposed for job creation in cities of China and other developing countries.