This paper takes the economic synchronicity of"city pairs"as an entry point,and integrates a panel dataset spanning from 2008 to 2021,encompassing prefecture-level cities,micro-enterprises,and migrant populations.We employ a Difference-in-Differences(DID)model to analyze the im-pact of urban agglomerations on economic synchronicity and ex-plore its underlying mechanisms based on theoretical analysis.The paper reveals that urban agglomerations exhibit a positive effect on urban economic synchronicity,and the conclusion re-mains robust after a series of robustness tests.Mechanism analy-sis indicates that urban agglomerations primarily enhance eco-nomic synchronicity by synchronization of innovation,conver-gence of factor allocation,and expansion of virtual agglomera-tion.In further analysis,we take endogeneity issues into ac-count,and revalidate the findings using population mobility data.
urban agglomeration developmentregional coordinationsynchronicity of economic