Opportunities and competition in thick labor markets: Evidence from plant closures
利用工厂倒闭导致工人失业的行政面板数据，研究发现城市中高就业密度带来的机会被更激烈的竞争所抵消，且竞争对失业时长的影响超过机会。
Abstract Since Marshall (1890), it has been widely held in urban economic theory that cities insure workers against the risk of unemployment by offering a larger pool of potential jobs. Using a large administrative panel data set on workers displaced as a result of plant closures, we examine whether positive effects from a higher urban job density are offset by more intense competition between workers. When controlling for the sorting of workers between regions, we find robust evidence that the effect of job competition on unemployment duration exceeds that of job opportunities in absolute value. Our results put the idea of urban risk‐sharing into perspective and provide an explanation for observed longer unemployment durations in cities.