Analyst recommendations and stock price bubbles

Abstract

This paper documents how analyst recommendations are related to periods of bubbles. We find a strong positive relation between the concentration in analyst buy recommendations and bubble continuation in two settings. First, we show a positive association between the concentration in buy recommendations and the tech bubble; the crash was associated with changes in buy recommendation concentration. Second, in an out-of-sample analysis of firms in multiple industries from 1994-2009, we show that analyst buy recommendation concentration predicts future return patterns that exhibit characteristics of a rational speculative bubble. While the evidence is not sufficient to conclude that analyst buy recommendations are the causal factor that perpetuates the mispricing, our findings suggest that, at a minimum, analysts do not act proactively to correct this form of mispricing in a timely manner.