Tuesday, November 17

Good calls

I'm fascinated by the endgame from this past Sunday night's game between the New England Patriots and the Indianapolis Colts, a contest won 35-34 by the home Colts on a late touchdown drive. You've probably already read about New England coach Bill Belichick's decision leading up to that drive, and seen dozens of pundits lining up to take shots at him for his choice, but let me set the scene.

The Patriots lead 34-28 with 2:08 remaining. They have the ball, 4th and 2, on their own 28 yard line. The Colts have one time out remaining. Conventional NFL strategy in this instance would be to punt the ball away, but as considerable football research shows, coaches punt the ball far too often. Belichick decided to go for it, knowing that a successful conversion for all intents and purposes ends the game in favor of his club. The Patriots came up inches short, and the Colts took the ball 30 yards into the end zone to win the game.

Naturally, reaction to BB's call was heavily critical, especially in the Boston area. This guy and this guy in the Boston Herald just absolutely teed off on Belichick. They talk of his "bizarre gamble," his "insanity," called him "foolish," and made a host of other attacks far more personal than analytical. Tony Dungy said that punting "really was no decision at all. It was a no-brainer." Trent Dilfer called it "ludicrous." A friend of mine called the move "indefensible."

Guess what: you're all wrong. Belichick made the choice that gave his team the best chance of winning the game. Thus, Gerry Callahan, when you wrote, "Belichick did not play to win the game. He did not coach to win the game," what you wrote was the exact opposite of correct. Nice work!

Why do I say this? Because I looked into the numbers instead of just blasting a move because it's not what coaches do or because I don't like Belichick personally. (Full disclosure: I do not especially like Belichick.) I estimated some rough percentages, surmised that going for it might have been the high-percentage move, then found where Advanced NFL Stats had done a much more thorough job. The NY Times' Freakonomics blog weighs in in favor of the Pats' coach as well. Let me quote ANFLS' excellent, concise piece at length, because I think it's instructive:

With 2:00 left and the Colts with only one timeout, a successful conversion wins the game for all practical purposes. A 4th and 2 conversion would be successful 60% of the time. Historically, in a situation with 2:00 left and needing a TD to either win or tie, teams get the TD 53% of the time from that field position. The total WP [expected winning percentage] for the 4th down conversion attempt would therefore be:

(0.60 * 1) + (0.40 * (1-0.53)) = 0.79 WP

A punt from the 28 typically nets 38 yards, starting the Colts at their own 34. Teams historically get the TD 30% of the time in that situation. So the punt gives the Pats about a 0.70 WP.

To summarize: using statistical analysis from years of NFL data, Belichick's call gave the Patriots a 79% chance to win. Punting would have given them a 70% chance to win. What were you saying, Gerry Callahan? Oh right, I forgot, you're a sportswriter, and you hate numbers, especially ones that don't jive with your cherished beliefs and interfere with their opportunities to rip on a coach. My bad.

That analysis is telling on its own, but there are also some circumstances here that tip the scales even more in favor of Belichick's call. For one, the Patriots have one of the league's best offenses and had already put 34 points on the board in this game. So while a typical 4th and 2 is successful 60% of the time, it's reasonable to suggest that the Patriots' chances were greater than that owing to their high-caliber offensive abilities. You can also bump up their conversion odds when you allow for the fact that it was, in the words of ESPN, actually just over one yard, and that it wasn't a goal-line situation. If you say, for instance, that the Pats had a 70% chance to convert, that puts their overall WP at 84%.

The other key circumstance is: Peyton Manning. Do you really want to give this guy the ball with a chance to beat you in the last two minutes? One has to believe that the Colts' scoring percentages are considerably higher than either of the league averages from either 66 or 28 yards away; as our friend at ANFLS points out, the Colts' offensive prowess also widens the gap between the two options in favor of going for it.

Statistically speaking, the choice is clear: going for it on 4th and 2 was the correct decision, and by a considerable margin. Despite this, I wouldn't have ripped Belichick for punting. I wouldn't have been in favor of it, of course, but I would not consider it to be a bad call. It's just not the best one. It's interesting how unbalanced the two sides on this argument have been: while Belichick's critics have been extremely vocal and absolute in their declarations (conveniently ignoring the fact that the 4th-down play came damn close), people like ANFLS, Freakonomics, and myself, who are armed with superior evidence in favor of our position, are simply suggesting that Belichick took the optimal approach, not that punting would have been some horrible awful event.

There's also a difference in the reaction to evidence between the two sides. After making my initial postulation, I sought out ANFLS because I figured he'd done a better analysis. It turned out to support my initial guess, but if the numbers had been reversed, I would be writing about how a punt was the better choice, not stubbornly defending my initial guess. I've shown these numbers to several gentlemen who opposed the decision to go for it, and neither has chosen to change his vantage point, which I find curious. I can assure you that Gerry Callahan wouldn't be swayed by the numbers, and I give you a guarantee that Trent Dilfer wouldn't budge either, even if they worked out to 100% WP by going for it and 0% WP by kicking. And that's too bad.

There are two things I'd like to say in conclusion. One is that I respect Belichick for his call. Even knowing fully that he'd be called out by scores of uninformed scribes who don't understand what it means to be loss averse if the move (I will not call the higher-percentage option a "gamble") failed, he selected the option that he (correctly) believed gave his club the best chance for victory. That they lost is not the key point here - 79% is not 100% - the key is that he played the probabilities well, and that's what good game managers do. Ask yourself how many people would have criticized him for punting had the Colts marched 70 yards for the score even though it was, as we've seen a suboptimal choice.

Finally, just for fun, read about Maurice Jones-Drew's endgame kneel-down, which was also a smart decision that significantly increased his team's chances for victory yet will no doubt be criticized heavily simply because it was non-traditional.

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