Given some of the decisions this past weekend, it appears the Body Snatcherization of Kirk Ferentz is nearly complete. "Go for it on fourth and one? Why not?" "Fourth and seven? No problem." Sure, there was still a decision to run out the clock with a minute left and timeouts in his pocket, but a complete Les Miles personality transplant takes time, so maybe by the Nebraska game we'll see this happen. In this week's look at the statistical side of the game, I'll look at some of those bold choices, as well as the other single plays that turned out to be most crucial to the outcome in terms of changing the win probability of the game.
* Win probability is a figure that is used to estimate the chances that a team will win a football game given a certain game situation (the down, distance, yard marker, time remaining, and score). WP figures derived from the Advanced NFL Stats generic model. The usual caveats apply about an NFL model not totally applying to college football, etc. etc. (see previous versions of this post for more on WP, or look around the Advanced NFL Stats website).
This was a huge play for Iowa, not only because it gained so many yards, but also because it converted a long 3rd down play. How did it happen? It was a confluence of a soft zone call by Michigan and a shallow crossing route by Davis:
It looks like the Wolverines were in a quarter-quarter-half type zone in back with their linebackers dropping in zone underneath. The middle linebacker for Michigan drops a little too far back and is then out of position for the tackle when Davis catches the pass near the line of scrimmage. One interesting wrinkle is how Kevonte Martin-Manley's "route" effectively sets him up to block the outside linebacker after Davis makes the catch, suggesting that this was a read to Davis all the way. Add in some speed by Davis and a bad angle by a cornerback, and you have a 44-yard catch. This play was followed up by another pass play that was almost as significant, a 20-yard completion to Marvin McNutt that was worth +.08 WP.
2) Iowa ball, 4th and 1 from the Michigan 39 yard-line, 7:47 left in first quarter, 7-6 Iowa; Iowa fails to convert 4th down: -.04 WP for Iowa
This was an interesting sequence of events. On 3rd and 3, Marcus Coker ran the ball for what looked to be either a first down or inches away from it. Here's a screen shot of his forward progress before the referees waved the play dead:
Maybe the angle is wrong or the ESPN first down line is off a bit, but it looks like Coker is very, very close to a first down. So it's understandable that Kirk Ferentz thought a quick QB sneak would almost certainly be enough to get the first down. How hard is it to get a few inches, right?
Well, somehow between the end of the 3rd down play and the beginning of the 4th down play, a yard disappeared for Iowa:
Now when Vandenberg attempts the QB sneak and gains maybe a few inches, Iowa is short the first down by about a yard. I call shenanigans.
With all that said, Iowa has shown a decided affection for the quick QB sneak on 4th down, and I just don't know if it's justified. There's a certain gain from surprise, but there are also times where the decision is unnecessarily rushed and important information goes unnoticed, like, say, that the refs shorted you by about a yard, or that Michigan has left the entire left side of the offensive line uncovered. It also reflects a kind of pathology among coaches that one needs to call a play that gets exactly the number of yards required in short yardage conversions.* Defensive coaches, not being dummies, react by placing 9 or 10 men at the line, creating the bizarre situation where the defense is offering the offense 10 or 20 yard plays in exchange for stopping 1-yard plays. It's risky to throw down-field in these situations, of course (no one likes to see a pass flutter incomplete on 4th down), but the payoff for a completed pass is potentially huge. At the very least, it might pay to try some runs away from the massed concentration of the defense.
* This happened late in the Alabama-LSU game, where Alabama had a 3rd in 2 in LSU territory and obediently ran right into the LSU line for a one-yard loss. Alabama then punted and the game went to overtime, where they lost. Also important about the Alabama-LSU game: some more proof that kicking field goals in college is a sucker's game: the Crimson Tide missed four field goals, including one taken from the LSU two yard-line (two of the field goals were pretty much no-brainers, though, given the yardage needed).
One last note: even if the execution wasn't great, the call for the conversion was a good one. Iowa stood to gain +.08 WP with a conversion, and lose .04 if they failed to convert, while a punt to the Michigan 10 would have left the WP situation unchanged for Iowa. This translates into a break-even percentage of 33% to go for it; i.e. if Iowa felt they could get that one yard more than a third of the time, they should have gone for it.
3) Michigan ball, extra point try, 2:14 left in first quarter, 7-6 Iowa; Michigan fails to convert: +.03 WP for Iowa
This failed extra point was not a huge deal, but still cost Michigan a little bit. The fact that Michigan would have needed to convert a two-point conversion at the end of the game in order to tie goes back to this mistake.
Of course, this means that if B.J. Lowery was guilty of pass interference on that 4th and 3, that play could have been quite significant in WP terms. If you assume that Michigan had a WP heading into the play of something like 15%-20%, and that their chances of scoring on the final untimed down would been good (say 75%), then their chances of winning overall would improve to something like 30% (.75*.75*.5) the benefit of a potential PI call would have been a 10%-15% in their chances of winning. Another way to look at it is that a no-call dropped Michigan's chances of winning to zero from 15%-20%. And maybe the best way to look at it is to take into account the cost of the call and the opportunity cost of the non-call -- that is, that getting the call might have increased their chances by 15% and not getting the call reduced their chances by 15%, so that single play was worth a hefty 30% swing in Iowa's favor. So I can understand why Michigan fans are upset about the call, but that just raises the question: was it pass interference? I didn't see anything egregious there, but I am of course biased. What's not in doubt is that the final play was indeed very crucial to the outcome of the game, given the leverage involved.