He started the game with a surprise onside kick and went for it on 4th down on the Chiefs first offensive drive.
The surprise onside kick is, statistically, almost never a bad idea. At the start of the game, we can just use expected points to analyze the decision. Surprise onside kicks are recovered 60% of the time. Last fall, I wrote (forgive the self quote):
"The EP for a failed onside attempt is -2.1 pts, and the EP for a success is +1.2 pts. At first glance it appears onside kicks are always losing propositions. But don’t forget that you’ve always got to kickoff somehow, and a normal kickoff averages -0.7 pts for the kicking team...Solving for the break-even success rate, where the combined expected points of an onside kick equal that of a normal kick, we get...42%."
This time it didn't work out, but it was still a good call. My only criticism is that this was the second time in two weeks Haley called for the surprise onside kick. Plus, if there is one team in the galaxy that's on guard for surprise onside kicks, it has to be the 2010 Indianapolis Colts.
Later in the first quarter, after an 8-minute-long grinding drive, Haley gave the go-ahead for a 4th and 2 conversion attempt on the Indianapolis 8. We already know it's a slam-dunk good idea in normal situations, but let's do a quick check using WP.
Two-yard conversions are successful inside the 10 55% of the time. A successful conversion gives the Chiefs at least a 1st and goal at the 6, worth a 0.56 WP. A failed conversion attempt gives the Colts a 1st down at the 8, and is worth 0.41 WP. On net, the conversion attempt is worth 0.49 WP.
FGs are good from the 8 95% of the time. A successful FG ties the game and gives the ball back to the Colts after a kickoff, worth 0.47 WP to the Chiefs. A miss gives the Colts a first down at their own 15, worth 0.40 WP for the Chiefs. On net, the FG attempt is worth 0.46 WP.
Going for it was probably the better call, especially if you think the Chiefs were underdogs. Underdogs need to take chances to win, and Haley seems to understand that. Congratulations, Todd. You've been named the Advanced NFL Stats Coach of the Week. Send me your shirt size, and you'll get a free one of these: