I had an email debate with a friend yesterday who doubted that NBA teams actually tank to get better draft position. He says that teams in all sports hold out some key players when the games stop mattering, and everyone is making too big a deal of this whole thing. (Although he made an allowance for Minnesota.)

On my to-do list for today was to assemble some kind of post to prove him wrong. My analysis was going to be based on stuff like how many players are missing games with lame reasons like "bruised" this and "sore" that. This is an hombre's league. You miss games with missing limbs. Soreness? WE ALL go to work sore sometimes, unless they don't want us at work.

But, praise be to David Berri, who wrote the book "Wages of Wins" and has saved me a lot of time-consuming amateurish research. On his blog yesterday, Berri quotes from his own book about this very topic:

Beck Taylor and Justin Trogdon [in an article published in 2002 in The Journal of Labor Economics] wondered how the incentive to lose altered the behavior of NBA teams. During the 1983-84 season, the year before the lottery was established, these authors­ found that teams eliminated from the playoffs were, relative to playoff teams, about 2.5 times more likely to lose. This result was uncovered after they controlled for team quality. In other words, non-playoff teams were found to lose more often than one would expect even bad teams to fail. When the lottery was instituted the next season, though, the increased tendency of non-playoff teams to lose vanished.

That is not the end of the story. In 1990 the NBA instituted a weighted lottery, where the odds of landing the top pick would improve the more the team lost. Once again, teams in the NBA had an incentive to lose. Once again Taylor and Trogdon report that after controlling for team quality, non-playoff teams were more likely to lose, although the size of the effect was smaller. With a weighted lottery non-playoff teams were only 2.2 times more likely to lose. Hence, as the incentives these teams faced were changed, the behavior changed as well.

Game. Set. Tank.