Fama vs. Thaler
By Arnold Kling
As for regulators, because the ECMH [Efficient Capital Markets Hypothesis] is often brought to bear as a justification for deregulation in politically charged policy disputes, such as mandatory corporate disclosure and insider trading, those who support regulation of such areas find comfort in the behavioral critique. One problem with such arguments, of course, is that it takes a theory to beat a theory, and no behavioralist theory yet advanced does a better job of explaining the vast bulk of stock market phenomena than the ECMH.
See also this blog entry by Larry Ribstein.
Those who align with Thaler suggest that privatizing social security would further misalign securities prices from value by bringing more irrational investors into the market.
For Discussion. Can imperfect government regulators protect imperfect investors from themselves?