Monetary policy, firm heterogeneity, and product variety
研究了紧缩性货币政策通过淘汰低效企业提高生产率，但减少产品多样性损害福利，且阻止新企业进入、保护现有企业会降低整体生产率，并用美国数据验证了货币政策对产品多样性的影响。
This study provides new insights on the allocative effect of monetary policy. It shows that contractionary monetary policy exerts an important reallocation effect by cleansing unproductive firms and enhancing aggregate productivity. At the same time, however, reallocation involves a reduction in the number of product variety that is central to consumer preferences and hurts welfare. A contractionary policy prevents the entry of new firms and insulates incumbent firms from competition, reducing aggregate productivity. We provide empirical evidence on U.S. data that corroborates the relevance of monetary policy for product variety resulting from firm entry and exit.