Not even Buffett and Zweig are perfect - The Globe and Mail

Not even Buffett and Zweig are perfect - The Globe and Mail: "When you're screening through thousands of stocks, you're going to end up buying some that end up being busts, and Mr. Zweig found that his approach had a built-in error rate of about three-eighths over the long term. “That is, out of eight stocks that I pick, three, or 38 per cent, will underperform the market,” he wrote. Of course, it would be great if you knew ahead of time which stocks fell into that 38 per cent. But no one can do that – and Mr. Zweig showed that you don't have to. Beating the market 62 per cent of the time netted him huge profits."