How informative are insider trades and analyst recommendations?
研究了内幕交易与分析师推荐之间的相互影响及信息含量，发现分析师推荐显著影响后续内幕交易，但反之不成立；两种信息信号互补，但内幕买入在某些情况下可替代分析师推荐的信息价值。
This study evaluates the interactions between, and informativeness of, insider trading and analyst recommendations. We find that analyst recommendations significantly affect subsequent insider trading, but not vice versa. Surprisingly, in aggregate, insiders buy more shares following analyst downgrades and sell more shares following upgrades. This pattern persists even after controlling for analysts’ momentum and insiders’ contrarian trading preferences. Analysts, in contrast, do not systematically take into account insider trading when revising their recommendations. More importantly, we show that these two information signals complement each other although insider buying could be a singularly strong signal that substitutes the informativeness of analyst recommendations under certain circumstances. Overall, our findings highlight the important dynamics and financial market consequences between the two crucial groups of information providers.