An empirical examination of matching theories: The one child policy, partner choice and matching intensity in urban China

► Overlap Index good at detecting minute changes in matching patterns. ► One Child Policy (OCP) raised incidence of positive assortative matching in marriage market. ► Simple GE model illustrates how OCP affects matching patterns. This paper introduces an index that facilitates the testing of differing matching theories based on the degree of overlap between a theoretically generated matching joint density and its empirical counterpart. The index is asymptotically Normal, consequently permitting inference. To demonstrate its use, the paper examines the effect the One Child Policy had on matching patterns in the marriage market in China. To distinguish between confounding policies of the period, a static general equilibrium model is introduced. It predicts that constraining marital output in the child quantity dimension may raise the marginal benefit of positive assortative matching and investment in child quality, thereby increasing the intensity with which they are pursued and concomitantly reducing the marriage rate. Upon verifying that the policy was binding via a Poisson model, using the matching index, significant support for increases in positive assortative matching and reductions in negative assortative matching were found.