中文摘要：

以城市群为单元的区域规划已经上升为国家战略，我国区域发展正在由“带状”转向“块状”，区域经济正在由省域、行政区经济转向城市群经济。基于2002-2013年城市数据，采用Dagum基尼系数、VAR格兰杰因果检验分析法实证考察了中国五大国家城市群经济发展的空间差异及溢出效应。结果表明：（1）五大城市群经济发展呈非均衡态势，由基尼系数刻画的经济发展相对差异呈总体下降趋势；（2）长江中游、京津冀城市群经济发展的区域内差异呈总体上升趋势，其他城市群区域内差异呈总体下降趋势；京津冀与长三角经济发展的区域间差异呈总体上升趋势，其他城市群区域间差异均呈总体下降趋势；区域间差异是总体差异的主要来源。（3）10％显著性水平下，珠三角、长三角城市群对京津冀、长江中游、成渝城市群具有单向溢出效应，京津冀、长江中游、成渝城市群之间存在两两双向溢出效应，珠三角、长三角城市群之间无显著溢出效应。

英文摘要：

Regional planning based on megalopolis has become a national strategy. Economic development of our country is changing from strip mode to block mode, and regional economy is changing from provincial and administrative region economy to megalopolis economy. Based on urban data from 2002 to 2013, this paper uses the methods of Dagum Gini coefficient and VAR Granger causality test to empirically examine the spatial differences and spillover effects of economic development of five megalopolises in China. Results show that： （1）The economic development of five megalopolises has obvious disequilibrium characteristics, and relative differences of economic development characterized by the overall Gini coefficient have a downward trend. （2）The differences within the region of economic development are increasing in the middle reaches of the Yangtze River and Beijing-Tianjin-Hebei megalopolises, and are descending in the other megalopolises. The differences between regions of Beijing-Tianjin-Hebei and Yangtze River Delta megalopolises show a rising trend, and the other differences among regions show downward trends. The differences among regions are the main sources of the overall differences. （3）At 10% significant level,there are unidirectional spillover effects from Zhujiang Delta and Yangtze River Delta megalopolises to the other megalopolises, and there are two-way spillover effects among Beijing-Tianjin-Hebei, the middle reaches of the Yangtze River and Chengdu-Chongqing megalopolises, and there are no significant spillover effects between Zhujiang Delta and Yangtze River Delta megalopolises.