Going for it on fourth down is a smart playBy PETE GRATHOFF
The Kansas City Star
Undoubtedly, some Chiefs fans initially questioned coach Todd Haley’s decision to go for it on fourth down in Sunday’s 16-14 victory at Cleveland.
The Chiefs faced a fourth-and-1 from the Browns’ 36 with 2 minutes to play. Rather than punt, the Chiefs instead handed the ball to Thomas Jones who got the first down.
Going for it on fourth down shouldn’t be a surprise to anyone who is familiar with a study done by University of California, Berkeley professor David Romer. In a 2002 paper, Romer determined that NFL teams would benefit from the kind of move Haley made Sunday.
“The results are striking,” Romer said after the paper was published. “The analysis implies that teams should be quite aggressive.”
Romer, an economics professor, found that on a team’s own half of the field, going for it is better on average as long as there are less than about 4 yards to go for a first down. After midfield, teams should generally be even more aggressive, he said.
In setting boundaries for his research, Romer looked at first-quarter plays so as to avoid the complications introduced when one team is well ahead of the other, or when the end of a half is approaching. He reviewed almost 20,000 plays from 732 regular-season games.
Taking into account that decisions to go for a touchdown on fourth down are so rare, he analyzed the outcomes of third-down plays instead to determine what to expect if teams went for it on fourth down.
Romer started by considering the number of points involved for a field goal or touchdown, and the probabilities of the success of a field goal and the odds of making a first down or touchdown. The catch, Romer wrote in his paper, is to think ahead about what happens next, and what happens after that, and after that — a process summarized by a tool known to economists as the “Bellman equation.”
To deal with this complication, Romer focused on 101 situations: a first down on each yard line, a kickoff from the 30-yard line, and a free kick from the 20-yard line following a safety. The Bellman equation and large data set allowed him to estimate an average value in terms of points for each of these situations.
When combined with information about the likely outcomes of kicking and going for it, these point values allowed Romer to determine which decision is better on average as a function of where the team is on the field and how many yards it needs for a first down or a touchdown.
That’s when Romer found that going for it on fourth down is actually a smart play, particularly in the situation the Chiefs found themselves on Sunday.
“This pushes for more high-stakes plays,” Romer told the New York Times. “The football analytics push you to a more aggressive, exciting game.”