Capitalizing on Catastrophe: Short Selling Insurance Stocks Around Hurricanes Katrina and Rita

We develop several hypotheses regarding short‐selling activity around Hurricanes Katrina and Rita. We find that abnormal short selling does not increase until 2 trading days after the landfall of Katrina and that short‐selling activity is much more significant around Rita. We find a substantial increase in short‐selling activity in the trading days prior to the landfall of Rita and relatively less short‐selling activity in the trading days after landfall. There is little evidence that suggests that traders short insurance stocks with more potential exposure in the Gulf region than other insurance stocks in the days before landfall.     

“奇绝”好品牌

你没有时间去认识所有把“你好”作为个性签名的人，也没有时间尝遍所有拥有“经典口味”的茶。一个好的品牌故事永远行走在风险的边缘，斥退贪欲，拒绝平庸。     

Informed or speculative: Short selling analyst recommendations

Christophe et al. (2010) find evidence of abnormal short activity prior to analyst downgrades and argue that short sellers may be violating SEC insider-trading laws by trading on information obtained from analysts about upcoming downgrades. However, observing abnormal shorting prior to downgrades is not tantamount to determining that short sellers are trading on tips from analysts unless shorting is abnormally low prior to upgrades. This paper revisits this issue. While we observe abnormal shorting prior to downgrades, we also find markedly higher shorting prior to upgrades. In fact, the short-selling patterns surrounding both downgrades and upgrades are remarkably symmetric indicating that short sellers during the pre-recommendation period are not unusually informed about the direction of upcoming recommendation changes. If anything, our findings indicate that short selling prior to analyst recommendations is more likely speculative than informed.     

Comparing the information in short sales and put options

Prior work shows that both short sales and put options contain information about future stock prices. In this study, we compare the return predictability in short sales to the return predictability in put options. The motivation for this comparison is based on the theoretical argument that informed traders can choose between short sales and put options when establishing short positions in a particular stocks. Results in this paper suggest that the underperformance of stocks with high short-selling activity is approximately four times larger than the underperformance of stocks with high put-option activity. While stocks that are most likely to face binding short-sale constraints drive the underperformance caused by put-option activity, we still find that short sales are generally more informative about future prices.