A

问题如下：

Which of the following best explains why it is unlikely a poor-performing hedge fund would be added to an index?

选项：

A.Survivorship bias B.Backfill bias C.Selection bias

解释：

Selection bias refers to when the benchmark inclusion criteria cover only those funds that have good performance and hence report their performance to attract new investors. A is incorrect; survivorship bias is when the benchmark stops including funds that have ceased operations, most likely due to poor performance, and hence does not fully represent the hedge fund universe. B is incorrect; backfill bias occurs when an index retroactively includes the performance of a fund before it is added to the index.

对冲基金的业绩评估会有各种bias：Survivorship bias是说只有还存在的对冲基金才会被统计业绩，那些已经清算的是不会被选进index的；Backfill bias是指当一个对冲基金被加入到index时，它以前的业绩也要进行统计，就好像一开始就存在在这个index中一样；Selection bias是指只有业绩好的基金经理才会选择披露业绩，才能被统计到index中。所以本题选C，它说明了为什么表现不好的基金不会被统计到index中。