Heterogeneity and Aggregation: Implications for Labor-Market Fluctuations
证明在只有生产率冲击的异质性主体模型中，总就业和消费可以随生产率上升，但两者相关性低，且边际替代率与生产率之间存在时变楔形，提醒人们不要将这种楔形视为劳动力市场失效或商业周期的根本驱动力。
We demonstrate that aggregate employment and consumption can increase without a corresponding movement in productivity in a model with heterogeneous agents where the only aggregate disturbance is a productivity shock. The interaction between incomplete capital markets and indivisible labor results in a low employment-productivity correlation and creates a time-varying wedge between the marginal rate of substitution (for commodity consumption and hours) and productivity. Our results caution against viewing the measured wedge as an inefficiency due to a failure of labor-market clearing or as a fundamental driving force behind business cycles.