中文摘要：

厘清大城市是否有利于小城市经济增长这一问题,对于贯彻大中小城市和小城镇协调发展的国家新型城镇化战略具有重要意义。以长三角108个小城市为例,在传统经济增长模型中加入到大城市的地理距离、行政边界、市场潜能等因素,估计不同等级的大城市对小城市经济增长的空间影响及其异质性。研究发现：临近大城市有助于促进小城市的经济增长,并未发现存在集聚阴影效应的直接证据;空间相互作用的方向更多体现为高等级城市对低等级城市的影响,来自副省级城市的增长溢出最为显著,同层级小城市之间的空间关联效应相对微弱;城市间存在一定程度的市场分割,行政边界的存在阻碍了空间溢出效应的发挥。最后从强化中心城市的辐射带动功能、促进不同规模城市空间溢出效应的全域性释放、破除行政区经济的束缚等方面提出了促进大中小城市和小城镇协调发展的政策启示。

英文摘要：

Promoting coordinated development among large, medium-sized, and small cities as well as small towns, is highly emphasized in Chinese National New Urbanization Plan.Therefore, it is of great significance to clarify the spatial interactions between cities from different hierarchies, and to confirm whether large cities are really conducive to the economic growth of small cities. However, previous empirical literatures mainly focused on the spatial spillover effect between cities from the same hierarchy, and neglected the heterogeneity of urban hierarchy. Furthermore, the sample of previous studies generally included all the provinces or prefecture cities in China, which led to the lack of exploration on the internal spatial interactions within urban agglomerations such as the Yangtze River Delta. Taking 108 small cities in the Yangtze River Delta as study samples, this paper examines the spatial spillover effects between cities from both same and different hierarchies, by adding geographical distance to different- hierarchy cities, whether within administrative boundary or not and market potentials into classic economic growth model. It is found that approaching large cities may contribute to the economic growth of small cities, and the agglomeration shadow hypothesized by the New Economic Geography is not supported in the Yangtze River Delta. This also means the economic growth of small cities is still under the influence of metropolitan areas, which demonstrates the necessity and benefits of metropolitan development strategy. Secondly, spatial interactions are more likely to happen between high- and lowhierarchy cities, whereas those between same hierarchy cities are relatively weak. The positive growth spillover effect from sub-provincial city on small cities is found to be most significant.Thirdly, the market segmentation caused by administrative boundaries weakens the spatial spillover effect. The small cities under the administrative jurisdiction of the nearest prefecture city receive lower economic growth ra