The Best Explanation of Survivorship Bias I've Read

Get a list of email addresses of people interested in sports betting. Say you have 32,000. Email 16,000 of them to say that the home team will win this week’s big team, and 16,000 to say the home team will lose. Now, half of the people will have gotten the correct prediction, and the next week, you do the same thing with them. After 5 weeks, you’ll have 1,000 email addresses of people who have seen you pick the winner five times in a row!. Now you pitch your 1-900 number or paid email list subscription to this amazed group.

The Distributed Republic, via a great post on stupid Wall Street performance-chasing tendencies from I Will Teach You To Be Rich.