Prior research examines the value and timing of analysts' activities in relation to earnings announcements. Ivkovic and
Jegadeesh (2004) find that many recommendation revisions happen within a few days of earnings announcements. They
show that the price reaction to recommendation revisions is weakest during the week after earnings announcements.
Altinkilic and Hansen (2009) likewise find that nearly a quarter of analysts' recommendation revisions follow earnings
announcements and another eighth of the revisions follow earnings guidance. They examine intra-day returns and
demonstrate that the returns previously shown to be associated with recommendations are contaminated by the effects of
pre-event news. Their results imply that analysts' recommendations are “information-free” for investors. Collectively, recent
evidence brings into question the value of analyst recommendations after earnings announcements and raises the question
as to why analysts issue revisions shortly after earnings are reported.