标题： 金融约束、风险分担与最优货币政策 显示英文标题

标题： Financial constraints, risk sharing, and optimal monetary policy

摘要： 我刻画了在一个具有不同类型的消费者以及银行和企业家部门内生金融约束的粘性价格经济中的最优政府政策。 由于抵押品约束中隐含的货币外部性和来自消费者类型异质性的其他外部性，竞争性均衡分配受到限制而效率低下。 这些外部性可以通过适当的财政工具来纠正。 无论这些工具是否可用，最优货币政策的目标是在长期内实现价格稳定，并在短期内接近价格稳定，这与传统的新凯恩斯主义环境一致。 与竞争性均衡相比，受约束的有效分配显著改善了代理人之间的风险分担，接近无约束的帕累托最优，并带来了显著的福利收益。 这种分配在银行和企业家部门的杠杆率较低，且不太容易出现分散经济中偶尔发生的繁荣-萧条金融危及零下界事件。 显示英文摘要

摘要： I characterize optimal government policy in a sticky-price economy with different types of consumers and endogenous financial constraints in the banking and entrepreneurial sectors. The competitive equilibrium allocation is constrained inefficient due to a pecuniary externality implicit in the collateral constraint and other externalities arising from consumer type heterogeneity. These externalities can be corrected with appropriate fiscal instruments. Independently of the availability of such instruments, optimal monetary policy aims to achieve price stability in the long run and approximate price stability in the short run, as in the conventional New Keynesian environment. Compared to the competitive equilibrium, the constrained efficient allocation significantly improves between-agent risk sharing, approaching the unconstrained Pareto optimum and leading to sizable welfare gains. Such an allocation has lower leverage in the banking and entrepreneurial sectors and is less prone to the boom-bust financial crises and zero-lower-bound episodes observed occasionally in the decentralized economy.