Econ Papers Daily / 工作论文
柠檬市场中的分选
Sorting in a Market for Lemons
摘要
Search frictions normally raise the bar for sorting: both random and directed search require complementarities strictly stronger than the supermodularity that suffices in Becker's (1973) frictionless model. We introduce private information into this setting: firms post wages without observing worker productivity, while better workers have better outside options, creating a market for lemons (Akerlof 1970). We show that this information friction pushes sorting the other way: attracting high-productivity workers without attracting low-productivity ones requires a higher wage paired with a lower job-finding probability, so vacancies fill faster. This strict ranking of vacancy-filling rates sorts the market positively whenever output is complementary in worker and firm quality. Becker's condition therefore suffices once more, and private information makes positive sorting easier to sustain than complete information does.
中文摘要
搜寻摩擦通常会提高分类的门槛：无论是随机搜寻还是定向搜寻，都要求互补性强于贝克尔（1973）无摩擦模型中足以实现分类的超模性。我们将私人信息引入这一框架：企业发布工资时无法观察工人生产率，而更优秀的工人拥有更好的外部选择，从而形成一个柠檬市场（阿克洛夫1970）。我们表明，这种信息摩擦将分类推向相反方向：要吸引高生产率工人而不吸引低生产率工人，需要以更高工资搭配更低的工作获得概率，从而使空缺职位更快被填补。只要产出在工人质量与企业质量之间具有互补性，这种对职位填补率的严格排序就会使市场实现正向分类。因此，贝克尔的条件再次足够，而私人信息使正向分类比完全信息下更容易维持。