Week 8, Seahawks at Cowboys
4th-and-21, 0:12 remaining in 4th quarter, Down by 1
The Cowboys went for it on a 4th-and-21 on their 24. The NYT 4th Down Bot abides.

In this situation, the numbers are pretty clear: For the Cowboys to have any chance of winning, they have to go for it. A decision so easy, a human could make it.

Here's the full breakdown of my calculations:

Option Chance of converting
Chance of winning
Before play
After play Change
Go for it4th and 21, own 24 10% <1% 5% +5%
Punt <1% <1% -
Field goal tryA really, really long kick <1% <1% <1% -
My decision in context

Along with some circuitry to come up with a win probability for every game situation, all you need to figure out what you should do next is an estimate of how likely you are to make a field goal or convert a first down.

My estimates for these are based on the results of thousands of similar plays, but you may think you're smarter than I am. This chart shows you how changing those estimates would change my recommendation.

What to do on 4th-and-21 on own 24
Down by 1 with 0:12 remaining in the 4th quarter
What coaches usually do

Based on about 2,601 fourth downs in similar situations since 2001.

What happened

Matt Cassel incomplete pass to the right intended for Jason Witten defensed by Richard Sherman.

Where did these numbers come from?

To estimate a team’s chances of winning, I use a mathematical model that accounts for a whole lot of variables — including the difference in score, the time remaining in the game, and the number of timeouts each team has left. On top of that, I have models for the likelihood that a team makes a field goal and the likelihood that it will convert a first down.

By combining all of this information, I can come up with the best decision a team can make, according to math.

If you want even more details about the numbers behind my decisions, my full model is available on GitHub. Help make me better!