Credit rating, post‐earnings‐announcement drift, and arbitrage from transient institutions
研究发现信用评级越低的企业，盈余公告后漂移现象越显著，且机构投资者虽试图套利但未能消除该现象，表明低评级企业的估值风险是漂移持续的原因。
Abstract This study first establishes a robust link between credit rating and post‐earnings‐announcement drift (PEAD). I find strong evidence that PEAD is more salient for firms with low credit ratings. This finding is consistent with the notion that investors are prone to underreact to earnings news from low credit rating firms that are characterized by high uncertainty of asset fundamentals. The association between credit rating and PEAD is not driven by traditional information uncertainty proxies such as earnings volatility, cash flow volatility, accruals quality, firm age, idiosyncratic volatility, and analyst forecast dispersion. I further investigate whether transient institutions exploit the differential of PEAD among different rated firms in their arbitrage trades. The results reveal that transient institutions tend to focus their arbitrage on low credit rating firms. However, the existence and concentration of PEAD in low credit rating firms suggest that transient institutions fail to arbitrage away PEAD among low‐rated firms and that the arbitrage strategy is riskier than expected by the transient institutions. This in turn implies that estimation risk associated with pricing the earnings news of low‐rated firms plays a substantive role in forming the strong PEAD of these firms.