Despite decades of careful data collection and mathematical and statistical research, on many large questions we have little more than rules of thumb. For example, we know that we should lower interest rates and inject liquidity to fight stagnation, and that we should raise policy rates and banks’ cash-reserve ratios to stifle inflation.
我们的经济专业知识在基础方法上是很局限的。以货币和财政政策为例，尽管几十年来我们都小心收集数据并进行数学和统计学研究，在很多大问题上我们也只不过是比一般经验知道得多一点而已。比如，我们知道为了对抗经济停滞应该降低利率并注入流动性，而且应该提高政策利率和银行存款准备金率以抑制通胀。有时候我们依赖自身的判断来结合利率行动与公开市场操作。但事实上我们对这些政策机制的了解还是很粗浅的。