Frictional Labor Markets: Theory and Implications

本研究建立了一个基于信息不完全的摩擦性失业理论。 人们认为，工人观察所有潜在雇主的特点是昂贵的。 相反，他们观察雇主的随机子集，选择最佳的样本量。 这个模型的均衡表现为摩擦性失业;一些工人失业，而一些符合条件的雇主有空缺。 然而，这个模型的影响更接近基线瓦尔拉斯模型比现有的摩擦失业模型不太坚实的微观基础。 除了得出一些新的和令人惊讶的结论外，这个理论还有一个易于处理的优点。 初步研究表明，使用这个模型来研究风险规避和不完善的劳动收入保险市场的摩擦性失业的影响的可能性。 由于不愿承担风险的失业工人消费他们的资产，他们越来越愿意寻找低工资、低生产率的工作，这些工作排队时间更短，就业机会更高。 因此，最佳求职行为意味着，短期失业的工人的预期工资远高于长期失业者的预期工资。 该模型也可以用来研究异质工人如何寻找异质工作。 以前的研究，集中在匹配过程中，而不是搜索过程中，表明无摩擦匹配或分配模型的结论不进行摩擦环境没有额外的假设。 然而，通过仔细模拟摩擦性失业背后的信息不完善，这一理论确立了无摩擦的结果推广到摩擦设置。 在任何时候，美国都有超过5%的劳动力遭受摩擦性失业，仅仅因为这个原因，了解这一水平是否是最佳水平就很重要。 但理解摩擦性失业之所以重要，还有其他原因：市场经济是否为失业工人找到工作提供了最佳激励，还是人们寻找工作效率低下，接受不合适的工作，还是拒绝合适的工作？ 摩擦性失业如何影响创造新就业机会或投资于人力和实物资本的激励？ 这个项目解决了所有这些问题，初步研究得出的结论与现有文献所建议的结论大不相同

This project builds a theory of frictional unemployment based on information imperfections. It is assumed that it is costly for workers to observe the characteristics of all potential employers. Instead, they observe a random subset of employers choosing optimally their sample size. The equilibrium of this model exhibits frictional unemployment; some workers are unemployed, while some eligible employers have open vacancies. However, the implications of this model are much closer to the baseline Walrasian model than to existing modals of frictional unemployment with less solid microfoundations. Besides reaching a number of new and surprising conclusions, this theory has the added advantage of tractability. Preliminary research shows the possibility of using this model to examine the implications of risk-aversion and imperfect labor-income insurance markets for frictional unemployment. As unemployed risk-averse workers consume their assets, they become increasingly willing to look for low wage, low productivity jobs where queues are shorter and employment chances are higher. Thus, optimal job search behavior implies that the expected wage of a worker who has been unemployed for only a short period of time, is much higher than the expected wage of the long-term unemployed who grow extremely risk-averse. This model can also be used to study how heterogeneous workers search for heterogeneous jobs. Previous research, which focused on the matching process and not on the search process, showed that the conclusions of frictionless matching or assignment models do not carry over to a frictional environment without additional assumptions. However, by carefully modeling the information imperfections behind frictional unemployment, this theory establishes that frictionless results generalize to a frictional setting. At any point in time, over 5% of the U.S. labor force suffer from frictional unemployment, and for that reason alone it is important to understand whether the level is optimal. But understanding frictional unemployment is important for other reasons: does a market economy give optimal incentives for an unemployed worker to take a job, or do people search inefficiently, accept inappropriate jobs, or reject appropriate ones? How does frictional unemployment affect the incentives to create new jobs, or to invest in human and physical capita1? This project addresses all these issues and preliminary research leads to substantially different conclusions than the existing literature suggests