| Development zones are an important regional industrial policy and a carrier of enterprise innovation in China,playing an important role in the process of reform and opening up for the first time.With the initiative of "mass entrepreneurship and innovation" and the imperative of accelerating the strategy of building an innovative country,development zones have once again become the focus of academic attention.In this regard,this study examines how and in what ways the establishment of national development zones affects enterprise innovation,and further investigates the impact of the establishment of different types and geographical locations of development zones on enterprise innovation through heterogeneity analysis.This paper uses panel data of listed enterprises from 1996-2019,and identifies whether an enterprise is in a development zone by its latitude and longitude and the four ranges of the development zone,and sets up a control group if an enterprise’s location does not change substantially within the observation interval and never enters the development zone;if an enterprise does not shift substantially within the observation interval and falls into the range of the development zone at a certain period,it is set up as an experimental group.This paper conducts the corresponding empirical study based on panel data and double difference model.The empirical results show that the establishment of development zones significantly contributes to firms’ innovation inputs,innovation outputs,and innovation quality.Further,the development zones are grouped into different types as well as different geographical locations for discussion.The heterogeneity analysis reveals that,in terms of the types of development zones,economic and technological development zones can promote enterprises’ innovation inputs and innovation outputs,high-tech development zones can stimulate enterprises’ innovation inputs,and special customs supervision zones effectively promote enterprises’ innovation tridimensional;in terms of geographical location,development zones in eastern and central regions can effectively stimulate enterprises’ innovation inputs,and development zones in western regions can effectively promote enterprises’ innovation tridimensional.In terms of geographical location,the development zones in the eastern and central regions can effectively stimulate enterprises’ innovation investment,and the development zones in the western region can effectively promote enterprises’ innovation.The mechanism analysis reveals that,in terms of the types of development zones,the establishment of economic and technological development zones improves enterprises’ innovation input and innovation output through the paths of "competition effect" and "supply chain concentration";the establishment of high-tech industrial development zones improves enterprises’ innovation input and innovation output through the paths of "tax incentives" and "supply chain concentration".The establishment of high-tech industrial development zones can effectively stimulate the innovation input of enterprises in the zones through "tax incentives","competition effect" and "supply chain concentration";the establishment of customs special supervisory zones can mainly stimulate the innovation input of enterprises in the zones through "government subsidies" and "supply chain concentration".The establishment of Customs Special Supervision Zones(CSZs)promotes the innovation input,output and quality of enterprises through "government subsidies" and "tax incentives".In terms of geographical location,the establishment of development zones in the eastern and central regions stimulates enterprises’ innovation investment through the "competition effect" and "supply chain concentration" path;the establishment of development zones in the western region stimulates enterprises’ innovation investment mainly through "government subsidies" and "competition effect".The establishment of development zones in the western region mainly promotes enterprises’ innovation input and output through "government subsidies","competition effect" and "supply chain concentration",and promotes enterprises’ innovation input and output through "government subsidies","competition effect" and "supply chain concentration".The "competition effect" promotes enterprises to improve the quality of innovation. |