基于百度指数的长江沿岸中心城市网络联系特征

The Network Connection Characteristics of Central Cities along the Yangtze River Based on Baidu Index

建立2012年、2017年百度指数矩阵,利用社会网络分析方法、泰尔指数、基尼系数和对数离差均值揭示长江沿岸中心城市网络联系的结构、类型、空间均衡性等特征。结果表明:(1)长江沿岸中心城市城际网络联系在长江经济带发展上升为国家战略后有明显增强;(2)城市网络联系层级由"1+5+9+12"分布演变为"3+3+11+10"的格局,上海、武汉、南京成为网络结构中的极核;(3)区域中六成以上城市还属于低点入度、低点出度的Ⅲ型城市,强化区域内城际联系任重道远;(4)城际网络联系强度在空间非均衡性上要远低于经济发展水平,但增长幅度上又远大于后者;这会增强区域经济发展的非均衡性,进而影响长江经济带协同发展,需要引起高度重视。

The Baidu index matrix for 2012 and 2017 was established,and the social network analysis method,Theil index,GINI coefficient and logarithmic dispersion mean were used to reveal the structure,type,spatial balance and other characteristics of network connections in central cities along the Yangtze River.The result shows that:(1) The intercity network of central cities along the Yangtze River significantly enhanced after the development of the Yangtze River Economic Belt has been upgraded to the national strategy.(2) The city network connection hierarchy distribution has evolved from the "1+5+9+12" distribution to the "3+3+11+10" distribution.And Shanghai,Wuhan and Nanjing became the polar cores of the network structure.(3)More than sixty percent of the cities belong to the type Ⅲ city with low in-degree and low out-degree,indicating that there is a long way to go to strengthen the connection between cities in the region.(4)The spatial disequilibrium degree of the city network connection strength is much lower than that of the economic development level,but the growth rate is much higher than the latter.This will enhance the imbalance of regional economic development,and then affect the coordinated development of the Yangtze River economic belt,which needs to be paid great attention to.