发表于 2009-05-19 22:36 IP属地：未知
In finance, Survivorship bias is the tendency for failed companies to be excluded from performance studies because they no longer exist. It often causes the results of studies to skew higher because only companies which were successful enough to survive until the end of the period are included.
For example, a mutual fund company's selection of funds today will include only those that have been successful in the past. Many losing funds are closed and merged into other funds to hide poor performance. This is how 90%[citation needed] of extant funds can truthfully claim to have performance in the first quartile of their peers: the other three quarters of funds have closed.
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