He wrote a paper making a statistical case that market volatility is too high for the efficient markets theory to be true. His idea was that markets have a tendency to overreact to news, or to react to non-news.
"This got me into a huge controversy then," he recalls. "I was wondering why do people get so emotional about this? I'm just saying something that's common sense and obvious - these markets aren't perfect."
http://www.bbc.co.uk/news/magazine-24579616
[WS:] What I find interesting about this subject is that apparently in economic facts are irrelevant until validated by The Theory. This is theology. -- Wojtek
"An anarchist is a neoliberal without money."