Efficience Informationnelle faible des Marchés Boursiers Africains

Abstract

In order to study the performance capacity of African countries markets, it is necessary to analyze the daily results of stock indices. For a period of six years, and based on four types of tests namely: Autocorrelation tests, runs tests, unit root and normality tests, the results obtained in a period of 1674days (from03/04/2013 to 18/12/2020) have shown and reported a mixed production of different indications. On the other hand, and at the level of the weak sense of efficiency, the African market return series indicate the low efficiency of the market. Overall, it is inferred that in African countries, daily stock index results do not follow a random walk; So it is concluded that due to the inefficiency of the market, insiders can get profit streams from arbitrage. On the other side, the concept of efficiency designates the right foot of the theory of modern finance; As a result, one can only confirm the existence of efficiency in the market if it deciphers and manifests all the information available and translated by each financial asset; in other words, the presence of efficiency expresses the capacity of the market to reconstitute its equilibrium and its persistence while allowing a better allocation of resources to investors. In other words, the presence of efficiency expresses the capacity of the market to reconstitute its equilibrium and persistence while allowing a better allocation of resources to investors. It is in the interest of explaining the doubt of the speed of information reflected in each stock exchange price that FAMA (1970) proceeded to the deconstruction of the efficiency in three sub-forms, namely: the weak form of the efficiency, the semi-strong form and finally the strong form