This paper uses a risk-shifting model to analyze policy responses to asset price booms. We show risk shifting leads to inefficient asset and credit booms in which asset prices can exceed fundamentals. However, the inefficiencies associated with risk shifting arise independently of whether the asset is a bubble. Given evidence of risk shifting, policymakers may not need to determine if assets are bubbles to justify intervention. We then show that some of the main candidate interventions against asset booms have ambiguous welfare implications: tighter monetary policy can mitigate some inefficiencies but at a cost, while leverage restrictions may raise asset prices and lead to more leveraged speculation rather than less. Policy responses are more effective when they disproportionately discourage riskier investments. (JEL D82, E23, E32, E44, E52, G01, G12)

中文翻译：

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资产价格繁荣和宏观经济政策：一种转移风险的方法

本文使用风险转移模型来分析对资产价格暴涨的政策反应。我们表明风险转移会导致资产价格可能超过基本面的低效资产和信贷繁荣。然而，与风险转移相关的低效率与资产是否为泡沫无关。鉴于风险转移的证据，政策制定者可能不需要确定资产是否为泡沫来证明干预的合理性。然后，我们表明，一些针对资产繁荣的主要候选干预措施具有模糊的福利影响：收紧货币政策可以减轻一些低效率，但要付出代价，而杠杆限制可能会提高资产价格并导致更多的杠杆投机，而不是更少。当政策反应不成比例地阻止风险较高的投资时，它们会更有效。（JEL D82、E23、E32、E44、E52、G01、