Abstract

HYME, Pauline. LA TEORÍA DE LOS MERCADOS DE CAPITALES EFICIENTES. UN EXAMEN CRÍTICO. Cuad. Econ. [online]. 2003, vol.22, n.39, pp. 57-83. ISSN 0121-4772.

E. Fama published an article in 1970 about " the theory of efficient capital markets" which had -and still has- a strong impact on finance. This article shows that Fama´s theory has little to do with efficiency as understood by economists. All that Fama really did was give a new name to a theory which had been around for more than a century, according to which the stock exchange is an " equitative game" or a martingale, as shown by Samuelson, conditioned by supposing expectations´ homogeneity. What Fama said about efficiency can only be explained by ideological reasoning, since it was proposed as part of the " new classics" anti-Keynesian offensive launched during the 1970s.

Keywords : efficient markets; expectations; speculation; economic methodology.