Reconciling Efficient Markets with Behavioral Finance: The Adaptive Markets Hypothesis

The battle between proponents of the Efficient Markets Hypothesis and champions of behavioral finance has never been more pitched, and there is little consensus as to which side is winning or what the implications are for investment management and consulting. In this article, I review the case for and against the Efficient Markets Hypothesis, and describe a new framework – the Adaptive Markets Hypothesis – in which the traditional models of modern financial economics can co-exist alongside behavioral models in an intellectually consistent manner. Based on evolutionary principles, the Adaptive Markets Hypothesis implies that the degree of market efficiency is related to environmental factors characterizing market ecology such as the number of competitors in the market, the magnitude of profit opportunities available, and the adaptability of the market participants. Many of the examples that behavioralists cite as violations of rationality that are inconsistent with market efficiency – loss aversion, overconfidence, overreaction, mental accounting, and other behavioral biases – are, in fact, consistent with an evolutionary model of individuals adapting to a changing environment via simple heuristics. Despite the qualitative nature of this new paradigm, I show that the Adaptive Markets Hypothesis yields a number of surprisingly concrete applications for both investment managers and consultants.

Editor’s Note: FinanceProfessor reference

Like this content? Why not share it?
Share on FacebookTweet about this on TwitterGoogle+Share on LinkedInBuffer this pagePin on PinterestShare on Redditshare on TumblrShare on StumbleUpon

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.