How Skilled Are Security Analysts?
研究发现多数证券分析师具备技能，但能力存在异质性；高、低类型分析师的推荐修正均有正异常收益，顶尖分析师因更多有影响力的推荐而表现更优。
ABSTRACT The majority of security analysts are identified as skilled when the cross‐section of analyst performance is modeled as a mixture of multiple skill distributions. Analysts exhibit heterogeneous skill—some are high‐type, and some are low‐type. On average, the recommendation revisions of both types exhibit positive abnormal returns. The heterogeneity stems from differential ability to produce new information; all analysts can profitably process news. Top analysts outperform because more of their recommendations are influential (i.e., associated with statistically significant returns) and both their influential and noninfluential recommendations are more informative. A majority of research firms are also identified as skilled.