Whatever It Takes? The Impact of Conditional Policy Promises
研究了政策宣布时市场对状态依赖政策行动的预期如何影响资产价格，发现对不利状态下更大支持的预期（政策看跌期权）解释了大部分政策宣布的影响。
At the announcement of a new policy, agents form a view of state-contingent policy actions and impact. We develop a method to estimate this state-contingent perception and implement it for many asset-purchase interventions worldwide. Expectations of larger support in bad states—“policy puts”—explain a large fraction of the announcements' impact. For example, when the Fed introduced purchases of corporate bonds in March 2020, markets expected five times more price support had conditions worsened relative to the median scenario. Perceived promises of additional support in bad states alter asset prices, risk, and the response to future announcements.