Week 3, Jets at Chiefs
4th-and-1, 10:04 remaining in 4th quarter, Down by 14
The Jets went for it on a 4th-and-1 on the Chiefs’ 21. The NYT 4th Down bot is totally on board, although attempting a field goal would have been fine, too.
If you disagree

I lean slightly towards going for it, but I don’t have strong feelings here – my numbers tell me that either going for it or attempting a field goal could be the best play. Specifically, attempting a field goal would be the right call if you think the Jets’ chances of converting on fourth down are less than 55 percent. (Based on my analysis, I’d give the Jets a 67 percent chance to get a first down here.)

Here's the full breakdown of my calculations:

Option Chance of converting
Chance of winning
Before play
After play Change
Go for it4th and 1, opp. 21 67% 6% 6% -
Field goal try38 yard kick (est.) 81% 6% 5% –1%
Punt 6% 3% –3%
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-1 on opp. 21
Down by 14 with 10:04 remaining in the 4th quarter
Behind my field goal number
What coaches usually do
Go for it 65% of the time
Field goal try 29% of the time
Punt 6% of the time
Based on about 851 fourth downs in similar situations since 2001.
What happened

Ryan Fitzpatrick pass to the right to Matt Forte for a loss of 3 yards to the KC24. Tackled by Derrick Johnson. Ryan Fitzpatrick pass to the right to Matt Forte for a loss of 3 yards to the KC24. Tackled by Derrick Johnson.

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!