A Quick Review of the 4th Down Decision

A Quick Review of the 4th Down Decision

Submitted by The Mathlete on November 19th, 2013 at 5:16 PM

I’m not touching the play call itself. Most of have pretty strong feelings about it. Criticizing a failed play in hindsight is usually a pretty lazy thing to do, but Michigan has a set of plays this year that have a firm history of no success and should never be run in critical situations.

But what about the decision itself to go for the 1st down. In the situation there were two possible choices and two possible outcomes for each.

Kick the FG Success/Failure
Go for the 1st Success/Failure

Each choice has an associated odds of success and each outcome has a resulting win odds.

Kick The FG

The safe, NFL worthy decision would have been to kick the field goal (“Take the points,” because field goals are never missed). In a low scoring game this probably gets you to overtime and there are no guarantees you get another chance or that you can take advantage of it. The downside is that with about 5 minutes to go, you are opening the door to give Northwestern the ball with plenty of time to drive the field and run out the clock.

A successful field goal means kicking off in a tie game with about 5 minutes left. In this situation, the team kicking off wins about 46% of the time. A made field goal would have made Michigan a slight underdog.

In the fourth quarter of close games, college kickers make 94% of field goals from inside the 5 yard line. Those are pretty good odds, but still a 1 in 16 chance that the kick is missed or blocked. A missed kick would have given Northwestern the ball at the 20 and dropped Michigan’s odds of winning to 23%.

Go for the First Down

Picking up positive yardage has been a challenge for Michigan the last month. Had they been able to convert for a first down their win odds would jump up to 70% (74% with a touchdown). Still plenty of time for a Northwestern touchdown, but definitely putting Michigan in the driver’s seat.

The failure to secure the first down left Michigan with a 34% chance at victory. Far from over but a lot of leverage on the play.

The Break Even Point

A field goal attempt would have given Michigan a 45% chance at victory once the small chance of a miss or block is factored in. With 70% odds with a first down and 34% odds if they failed to get the first down, Michigan would need to be able to have at least a 30% chance of success to break even on going for the first down. Michigan has had its troubles on offense but a 30% break even point is a low bar. 3rd or 4th and 1’s from inside the 5 are converted at 57% historically. So even if Michigan was half as likely as an average team to convert it still would have been an even decision with kicking the field goal.

If the numbers seem too high or too low there are a couple of follow up dynamics in play. A failed fourth down would have left Northwestern with the ball and the lead late. Coaching history as taught us that this is a recipe for most coaches to curl up into a ball and try and ground out the clock and if they’re lucky get a first down or two. Because of this often failed mentality, giving the other team back the ball with a lead can be more valuable than giving them back the ball with a tie where there is some pressure to push forward.

I think this was absolutely the correct decision to go for the first down in the situation even if the “execution” was less than ideal.

Going on 4th/onside kick theory gaining MSM steam

Going on 4th/onside kick theory gaining MSM steam

Submitted by Gulo Gulo Luscus on November 10th, 2010 at 5:09 PM

We've certainly seen much more detailed, stats-based posts regarding the matter of onside kicks and never punting, but MSM is starting to come around.  "Conventional wisdom" be damned...