关键词: 市场分割, 全要素生产率, 国内大循环

Abstract: This article systematically analyzes the productivity effect of market segmentation and its realization mechanism as well as specific change path from both theoretical and empirical perspectives，which not only overcomes the shortcomings of the inverted Ushaped hypothesis in theoretical logic and empirical analysis，but also finally solves the policy paradox it brings It is found that market segmentation will directly improve local productivity on the one hand，and indirectly hinder the improvement of local productivity by increasing the number of enterprises in the region on the other hand Under the joint effect of these two mechanisms，the impact of market segmentation on local productivity shows significant time heterogeneity，and will reduce the level of longterm productivity On this basis，the above theoretical hypothesis is verified by using the panel data variable coefficient regression model and dynamic spatial lag model，and it is found that the above conclusions are still robust even considering the spatial spillover effect of regional productivity Therefore，rather than bear the longterm efficiency loss caused by market segmentation，it is better to gradually eliminate market segmentation，and realize the smooth flow of domestic circulation

Key words: market segmentation, total factor productivity, domestic circulation