Leaning-against the-wind (LAW) policies, whereby interest rates are raised in the face of a growing asset price bubble, are often advocated as a means of dampening such bubbles. On the other hand, there are theoretical arguments suggesting that such a policy could have the opposite effect (Gal í, 2014). We study the effect of monetary policy on asset price bubbles in a laboratory experiment with an overlapping generations structure. Participants in the role of the young generation allocate their endowment between two investments: a risky asset and a one-period riskless bond. The risky asset pays no dividend and thus the possibility of selling it to the next generation is its only source of value. Consequently, its price is a pure bubble. We study how variations in the interest rate affect the evolution of the bubble in an experiment with three treatments. One treatment has a fixed low interest rate, another a fixed high interest rate, and the third has a LAW interest rate policy in place. We observe that the bubble increases (decreases) when interest rates are lower (higher) in the period of a policy change. However, the opposite effect is observed in the following period, when higher (lower) interest rates are associated with greater (smaller) bubble growth. Direct measurement of expectations reveals that traders expect prices to follow previous trends and tend to correct for prior errors in their predictions.

逆风（LAW）政策，即在资产价格泡沫不断扩大的情况下提高利率，通常被提倡作为抑制这种泡沫的手段。另一方面，有理论论据表明这种政策可能会产生相反的效果（Galí，2014）。我们在具有重叠世代结构的实验室实验中研究货币政策对资产价格泡沫的影响。扮演年轻一代角色的参与者在两种投资之间分配他们的禀赋：风险资产和一次性无风险债券。风险资产不分红，因此将其出售给下一代的可能性是其唯一的价值来源。因此，它的价格是一个纯粹的泡沫。我们在三个处理的实验中研究了利率的变化如何影响泡沫的演变。一种处理具有固定的低利率，另一种具有固定的高利率，第三种具有到位的 LAW 利率政策。我们观察到，在政策变化期间，当利率较低（较高）时，泡沫会增加（减少）。然而，在接下来的时期观察到相反的效果，当更高（更低）的利率与更大（更小）的泡沫增长相关时。对预期的直接测量表明，交易者期望价格跟随先前的趋势，并倾向于纠正他们预测中的先前错误。我们观察到，在政策变化期间，当利率较低（较高）时，泡沫会增加（减少）。然而，在接下来的时期观察到相反的效果，当更高（更低）的利率与更大（更小）的泡沫增长相关时。对预期的直接测量表明，交易者期望价格跟随先前的趋势，并倾向于纠正他们预测中的先前错误。我们观察到，在政策变化期间，当利率较低（较高）时，泡沫会增加（减少）。然而，在接下来的时期观察到相反的效果，当更高（更低）的利率与更大（更小）的泡沫增长相关时。对预期的直接测量表明，交易者期望价格跟随先前的趋势，并倾向于纠正他们预测中的先前错误。