Do Analyst Stock Recommendations Piggyback on Recent Corporate News? An Analysis of Regular‐Hour and After‐Hours Revisions
研究发现仅27.9%的分析师推荐修订方向性地确认了前期公司新闻，且这些修订促进了信息发现而非简单搭便车；盘后修订占样本70%，主要由机构客户需求驱动，其价格反应显著大于常规时段修订。
ABSTRACT Analysts often update their recommendations following corporate news. Questions have been raised regarding analysts’ ability to generate new information beyond recent corporate events. Employing a comprehensive database on corporate news, we show that only a small minority, or 27.9%, of all recommendation revisions directionally confirm the information in the preceding corporate events and even these “confirming revisions” facilitate the information discovery of corporate events and thus cannot simply be dismissed as “piggybacking.” Our analysis further shows that analysts not only facilitate price discovery to corporate news through issuing trending revisions but also help reverse prevailing market sentiments following corporate news by issuing contrarian revisions. Our study is the first to investigate short‐window intraday market reactions to revisions issued after hours, which account for 70% of all recommendation revisions in our sample period. Analysts’ incentives to issue revisions after hours appear to reflect demands from large institutional clients, who dominate after‐hours trading. More importantly, we show that the after‐hours revisions are associated with significantly greater price reactions and different price reaction patterns than revisions issued during regular trading hours. Collectively, our evidence indicates that analysts are a significant source of new information beyond recent corporate news and they also help shape the market's assessment of corporate disclosures.