Apport de la finance comportementale a l'analyse de la volatilite excessive des cours boursiers cas de la BRVM. (Contribution of behavioural finance to the analysis of excessive stock price excessive volatility: the case of the BRVM.
<b>French Abstract:/b> L'objet de cet article est de mettre en evidence l'existence d'une finance comportementale comme alternative a l'efficience informationnelle a travers l'apport de la finance comportementale a l'analyse de la volatilite excessive des cours boursiers dans le cadre de la BRVM. Volatilite excessive qualifiee par Shiller (2000) d'exuberance irrationnelle. L'etude empirique porte sur deux echantillons collectes sur Bloomberg, et sont repartis comme suit (1) un echantillon regroupant toutes les actions de la BRVM, observees durant la periode 2000 2018. (2) un echantillon qui totalise 21 actions observees entre janvier 2005 et decembre 2018. Les resultats auxquels nous sommes parvenus, montrent l'existence d'une volatilite excessive issue d'une relation synchrone entre le volume de transaction du a des echanges des investisseurs sur confiants, et la volatilite conditionnelle des rendements du marche.<br>Mots cles Efficience, Volatilite excessive, Finance comportementale, Exces de confiance, Comportement gregaire, GARCH et BRVM.<br><br><b>English Abstract:/b> The purpose of this article is to highlight the existence of behavioural finance, as an alternative to informational efficiency, through the contribution of behavioural finance to the analysis of excessive stock price volatility in the framework of the BRVM. Excessive volatility qualified by Shiller (2000) as irrational exuberance. The empirical study is based on two samples collected on Bloomberg, and is distributed as follows: (1) a sample of all BRVM actions observed during the period 2000 2018. (2) a sample totalling 21 actions observed between January 2005 and December 2018. The results show the existence of excessive volatility resulting from a synchronous relationship between the volume of transactions due to overconfident investor trading and the conditional volatility of market returns.