Yglesias

Garbage In, Double-Garbage Out

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CREDIT:

ESPN.com’s John Hollinger playoff predictor seems like an uncommonly dumb feature. It starts by using his interesting but flawed PowerRankings formula and then “Based on those rankings, each day the computer plays out the remainder of the season 5,000 times to see the potential range of projected outcomes. The results reveal the most likely win-loss record for each team — and how likely it is for each team to make the playoffs, win the NBA title, win the lottery, and so on.”

All this serves to do, however, is exaggerate flaws in the original model by compounding them over and over again.