Adapting financial rationality: Is a new paradigm emerging?

Abstract

We discuss the implications of an alternative to the efficient market hypothesis (EMH) the adaptive market hypothesis (AMH). The AMH advances a theoretical basis for a new financial paradigm which can better model such phenomena as the recent financial crisis. The AMH regards the financial market order as evolving, tentative and defined by creative destruction in which trading strategies are introduced, mutate to survive, or face abandonment. The concept of investor rationality is less helpful than the distinction between investment strategies which are more or less well adapted to the prevailing market environment. We outline how a more systematic and grounded basis for behavioural finance can be developed in line with the latter approach. Based on this we develop testable hypotheses allowing the AMH to be distinguished from the EMH. Finally, we discuss how the AMH can aid our understanding of important issues in finance. A central insight is that in the survival of richest, as opposed to fittest, implied by the AMH there is much room for misallocation of resources as price and value uncouple. In this shifting financial market order the regulatory State features as a further market in which the vote market verifies or disrupts market conditions.