On-the-Job Search, Mismatch and Efficiency*
分析了一类包含双方异质性和在职搜寻的搜寻模型的均衡，发现无承诺的买方垄断工资设定会产生“抢生意”外部性，导致过度职位创造；而有承诺时该外部性消失。
This paper characterizes the equilibrium for a large class of search models with two-sided heterogeneity and on-the-job search. Besides the well-known congestion externalities, we show that on-the-job search in combination with monopsonistic wage setting <it>without</it> commitment creates a “business-stealing” externality. In the absence of congestion effects, this leads to excessive vacancy creation. Under wage setting <it>with</it> commitment this externality is absent because when posting a wage, firms take into account the expected productivity of future workers in their current jobs. If firms are able to make and respond to counteroffers, then they will not have to pay no-quit premia and this also leads to excessive vacancy creation.