英文文献：Fama on bubbles-法玛在泡沫
英文文献作者：Tom Engsted
英文文献摘要：
Eugene Fama has repeatedly expressed his discontent with the notion of an irrational bubble. However, he has never publicly expressed his opinion on rational bubbles. This is peculiar since such bubbles build naturally from the rational efficient markets paradigm that Fama strongly adheres to. On empirical grounds Fama rejects bubbles by referring to the lack of reliable evidence that price declines are predictable. However, this argument cannot be used to rule out rational bubbles because such bubbles do not necessarily imply return predictability. On data samples that include the 1990s, there is evidence of an explosive component in stock market valuation ratios, consistent with a rational bubble.

尤金?法马(Eugene Fama)多次表达了他对非理性泡沫概念的不满。然而，他从未公开表达过自己对理性泡沫的看法。这很奇怪，因为这种泡沫是根据法玛强烈坚持的理性有效市场范式自然形成的。基于经验主义，法玛认为价格下跌是可以预测的，但缺乏可靠证据，因此拒绝了泡沫。然而，这一论点不能用来排除理性泡沫，因为这样的泡沫并不一定意味着回报的可预测性。在包括上世纪90年代的数据样本中，有证据表明，股市估值比率存在爆炸性成分，这与理性泡沫相符。