Yifan Wang

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A project is a continuum of ordered tasks that all have to be done, so the margin is not how much of each task to buy but who covers which. Two costs sit at the boundary between tasks: what a worker pays for the training she lacks, and what a pair pays to hand work across. Cheap metered cognition compresses both, at different rates, and team size depends on the two only through their ratio. A within-task gain therefore moves output without moving organization, while a boundary gain moves both — the two channels are indistinguishable in aggregates and opposite in organization. Teams dissolve while a prerequisite is still twice as expensive as a handoff.

with Chang Gao  ·  [Hide]

LGFV issuance spreads rise with local government leverage — under OLS, under a predetermined maturity-rollover instrument, and under the 2015 central-government debt swap. Housing-price growth is hump-shaped in leverage and turns negative past 18–23% of GDP. We read these patterns through a general-equilibrium model in which a leverage-dependent financial friction creates a debt threshold beyond which infrastructure investment collapses, so the bust needs no exogenous shock.

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Some desirable jobs are not priced. They are rationed by quota and handed out by examination: in 2021 China’s civil service took about 20,000 people from 1.5 million applicants. This paper models entry into such a sector alongside wage-clearing sectors and an outside option. Admission rises with an applicant’s rank inside the pool of people who chose to apply, so the admission rate is an equilibrium object rather than a parameter. Neither instrument is monotone. A more generous outside option at first enlarges the queue, since it makes failing cheaper to risk; past a threshold it is simply taken instead. A larger prize at first improves selection and then dilutes it, as the marginal applicants arrive from further down the ability distribution. The two humps have different engines: one works on the size of the queue and survives with the admission schedule held fixed, the other on who is in the pool. Because both instruments move that pool, they cannot be set apart from each other.

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Firms in a multi-country, multi-sector production network hold inventories of intermediate and final goods. Endogenizing that choice gives global shocks a propagation channel separate from trade itself. Under restrictions the economy is isomorphic to standard multi-sector models with input-output linkages.