【Paper】

Abstract: We develop a quantitative general-equilibrium framework for the normative evaluation of minimum wages in spatial economies with monopsonistic labour markets. We quantify the model for German micro-regions and successfully over-identify its predictions against the effects of the 2015 German minimum wage observed in data. Simulating the model, we find that at low levels, spatially blind national minimum wages can increase welfare and spatial equity simultaneously. At higher levels, however, welfare gains are traded against employment losses and spatial inequality. Because regional minimum wages are not spatially blind, they can increase employment and welfare in a spatially neutral manner.

KIER Seminar（Joint with Applied Microeconomics Seminar)

abstract: Low fertility is a pressing concern in many advanced economies, particularly those where gender gaps in work and caregiving persist. Recent research highlights that fertility increasingly depends on whether men can credibly share childcare responsibilities. This paper examines whether mandating paternity leave can raise fertility by institutionalizing fathers’ caregiving. We study a 2017 company-wide mandate at a large South Korean conglomerate requiring all male employees to take one month of fully paid paternity leave. Using newly linked administrative data and an event-study design, we find that the mandate sharply increased leave uptake, lengthened leave durations, and generated spillovers among fathers not directly subject to the policy. The probability of having a child rose by about 15 percent, with the largest effects among dual-earner couples and those with higher-earning, longer-tenured wives. Wives’ employment remained stable, indicating that fertility gains did not come at the cost of women’s careers. Complementary survey evidence shows more supportive workplace norms toward fathers’ leave-taking and greater paternal involvement in childcare at treated firms. These findings demonstrate that mandating short paternal leave can normalize fathers’ caregiving and promote fertility without undermining women’s employment.

要旨：Intermediaries often bundle credit and trade, from rural traders to digital platforms. This study investigates the equilibrium impacts of expanding external finance (e.g., microfinance) within these intermediated markets.
We develop a simple model, illustrated in a village setting, where farmers trade with either small buyers or dominant, financially interlinked middlemen. Providing external credit to poor farmers strengthens their option to sell to small buyers and intensifies competition faced by the middleman.
In equilibrium, the middleman responds by shrinking its network, reducing allocative efficiency and potentially making farmers worse off. By contrast, financing middleman entrants or richer farmers can better align incentives and improve welfare, highlighting the role of interlinked market structure in financial inclusion.

Abstract: This paper examines the role of labor market power in a spatial context. Using firm-level markdowns estimated from Chinese micro-level data, we find that migration has a significant effect on wage markdowns. We further investigate the underlying mechanisms, highlighting the critical role of migration in shaping the spatial structure of China’s labor market.