Polycentric Spatial Development Model and Firms' Export Product Quality Upgrading : Evidence from Chinese manufacturing firms

With the deepening of global specialization division of labor, China should shift from attaching importance to the scale of exports to attaching importance to the upgrading of export product quality. A reasonable and orderly polycentric network breaks the market barriers between regions and enables resource elements to be integrated and reconfigured on a larger geographical scale, which is an important internal driving force for upgrading the quality of firm export products. Based on this, this paper combines urban night lighting data, Chinese industrial firm data, and customs data to study the influencing factors and the mechanism of action of firms' export product quality upgrading from the perspective of regional spatial structure. The study shows that there is an inverted U-shaped relationship between polycentric spatial structure and the upgrading of firm export product quality, and this conclusion still holds after a series of robustness tests. Further study found that the opening of high-speed rail and the use of the Internet play a significant positive moderating effect in the process of polycentric development model influencing the export product quality of firms, while the distance between cities in the province plays a non-linear moderating effect. Meanwhile, the "labor allocation effect" and "innovation promotion effect" are effective mechanisms for the polycentric spatial structure to promote the upgrading of firms' export product quality. The findings of this paper help to improve the international trade competitiveness of Chinese firms from the perspective of urban planning