Increased competition, questionable accounting practices and a small free float were all known for months, Groupon just got hammered as the next high-betastock fallen victim to the "risk-off" mode.
If the market rises by 10%, and a stock rises by 20%, it's said to have a beta of 2.
如果股市涨了10%，股票涨了20%，那么该股的贝塔值就是2。
3
We'll come back to this, but beta of the stock is a measure of how much it moves with the market and the alpha of a stock is how much it outperforms the market.