Véronique Bessière and Michael Kaestner (2008)
Sur- et sous-réactions des analystes financiers : une étude des évolutions post-krach
Banque et Marchés, 91.
Overreaction and underreaction in analysts’ forecasts: a pre versus post-crash investigation -
The financial markets crash, which occurred March – April 2000 has aroused suspicion about financial analysts’ forecasts accuracy which could have made them more cautious, perhaps pessimistic about future performance. This article investigates the possibility of recent behavioral changes by examining analysts’ reactions to good and bad news before and after the crash. We analyze the interaction between over- and under-reaction and the optimistic bias following Easterwood and Nutt (1999)’s methodology. If the crash leads analysts to be less prone to optimism (or even pessimism), we might observe weaker underreaction (or possibly overreaction) to bad news and weaker overreaction (or possibly underreaction) to good news. Our results indicate a strong decrease in optimism after the crash. Reactions to new information are consistent with a reduction in optimism: analysts’ systematic underreaction to negative information strongly decreases after the crash. Overreaction to positive information, less pronounced before the crash, is also weakened.