We consider a macroprudential approach to analyze the optimal lending policy for the central bank, focusing on spillover effects that policy exerts on money markets. Lending against high-quality collateral protects central banks against losses, but can adversely affect liquidity creation in markets since high-quality collateral gets locked up with the central bank rather than circulating in markets. Lending against low-quality collateral creates counterparty risk but can improve liquidity in markets. We illustrate the optimal policy incorporating these trade-offs. Contrary to what is generally accepted, lending against high-quality collateral can have negative effects, whereas it may be optimal to lend against low-quality collateral.

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最后贷款人的抵押品理论*

我们考虑采用宏观审慎方法来分析央行的最优贷款政策，重点关注政策对货币市场的溢出效应。以高质量抵押品贷款可以保护中央银行免受损失，但可能会对市场的流动性产生不利影响，因为高质量的抵押品会被中央银行锁定，而不是在市场上流通。以低质量抵押品贷款会产生交易对手风险，但可以提高市场的流动性。我们说明了包含这些权衡的最佳策略。与普遍接受的相反，以高质量抵押品贷款可能会产生负面影响，而以低质量抵押品贷款可能是最佳选择。