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Ten thousand seasons with no wildcards

Posted by Doug on June 28, 2006

A few weeks ago, I did several posts (I, II, III, IV) on the idea of simulating a bunch of NFL seasons and seeing what kind of crazy stuff happens.

I had intended to play Tagliabue and implement various alternative playoff systems, then observe how things played out. Programming new playoff formats turned out to be tougher than I expected, so I tabled it.

But now I have finally gotten around to implementing at least one: in this post I'm going to eliminate the wildcard. Byes are no more and the eight division winners will play a standard tournament.

My first reaction would be to suspect that the more teams you let in the playoffs, the more you decrease the chance of the best team winning it. Therefore I'd guess that the wildcard reduces the chance of the best team winning it all. But it's not clear. In baseball, the wildcard adds an extra playoff round for every team, but that's not necessarily so in football. If the best team is a #1 or #2 seed, then the existence of wildcard teams doesn't affect their chances much. They still just have to win three games. If the best team is a #5 or #6 seed, then the existence of the wildcard obviously increases their chances, from zero to nonzero. So the only scenario in which the wildcard system decreases the best team's chances is if they are the #3 or #4 seed.

Let's recall how often the best team wins in the current format. If you believe the model, it's about 24% of the time. The second-best team wins about 14.5% of the time. In ten thousand runs, this is how often each of the top ten teams won the Super Bowl:

Tm# SBwins
1 2399
2 1448
3 1060
4 846
5 670
6 584
7 464
8 388
9 327
10 285

Here's how it goes with no wildcards:

Tm# SBwins
1 2246
2 1431
3 1074
4 827
5 625
6 562
7 488
8 386
9 334
10 294

Almost no change at all. That's remarkable. Whether you think 23% is too high or too low, everyone ought to favor the current wildcard system. It gives us four extra postseason games every year without meaningfully altering the chances of the best team winning. Well done, NFL.

I'll bet if we added two more wildcard teams and turned the postseason into a 16-team tourney, the best team's chances would plummet. I'll put that on the to-do list.

This entry was posted on Wednesday, June 28th, 2006 at 4:29 am and is filed under Statgeekery. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.