Comments on Advanced NFL Stats: The 4th Down Study - Part 1

I was familiar with the statistical arguments, and...

2012-01-28T05:07:14.321-05:00

I was familiar with the statistical arguments, and in broad agreement, but having just read the original post I am surprised no one has made more of the 'expected utility' concept in understanding why coaches do not go for it more often.

The key to the 'driving to work' analysis is not the time, it is 'work'. Obviously the difference between 19 and 20 minutes isnt enough to be worth the risk. But even assuming the average were weighted more toward the highway, the point is that if your boss is going to pay far more attention to the time you are late by 5 or more minutes, and far less to all the times you are on time or indeed early. In this sense, a football coach has to worry not only about his 'boss' but all those who mediate his boss' reactions (other owners, execs, coaches, and media) and also the indirect 'boss' of fan reaction, again mediated, but of significance especially when it leads to empty seats.

Were there a way to quantify a scale of effect of negative impact versus job security it might help commuters, if not coaches.

Brian, excellent stuff. I've always intuitivel...

2011-09-14T11:02:15.589-04:00

Brian, excellent stuff. I've always intuitively thought it makes sense to go for it in a lot of 4th down situations, but never seen any analysis before yours. In fact I thought teams would be more efficient overall if punting wasn't an option. Looking at your final chart, simplified recommendations would be always go for it within 2 yards, and within 5 in your opponents half of the field. I guess it's a little like basic strategy for blackjack, but easier. I think part of the problem has been an indoctrination into thinking of football as a 3 down game rather than 4, consciously or otherwise. Do you think the new kick-off position will alter your 0.7 point valuation much?

So I've done my own number-crunching, based mo...

2011-03-14T21:36:41.398-04:00

So I've done my own number-crunching, based more on the probability that the receiving team takes it back to the original punting yard of scrimmage: http://fourthandfortytwo.blogspot.com/2011/03/going-for-it-numbers-against-punting.html . Basically, what I found out is it all starts to break down right around mid-field, and really, for anything less than 2 yards to go.

Nomination for worst 4th down decision of the year...

2010-10-10T21:38:52.513-04:00

Nomination for worst 4th down decision of the year so far goes to Sean Payton for punting on 4th and 2 with 5 mins left in the game down by 10 lol

What most people don't know, but should is tha...

2010-08-22T11:29:06.132-04:00

What most people don't know, but should is that football is like a coin that has two sides. Everyone knows the universal truth of the first side of the coin that says that a team that scores more points than the opponent always wins. What people don't know is how a team lost a game without factoring the score. The other side of the coin would say that the team with the most real turnovers always losses the game. Statisticians do not count all events that turn the ball over without first scoring atleast 6 points. If they did they would see that the team with the higher number always losses. Try this with any game and you will see that it works:

Complete Turnovers: Interceptions, fumbles lost, missed fg's, punts, 4th down fails, kickoffs lost, safeties, and turnovers due to time (given if the team in possesion at the end of the half failed to score and has to kick to start the second half. Not counted if another turnover half or whole occurs at the same time. Also when the game ends and the team trailing fails to score before the time expiresn not counted against the team with the lead. also nullified if another turnover takes place.

Half Turnovers: Failed extra point or 2pat, Successful field goal, 2point conversion allowed.

This is an interesting discussion no doubt, but it...

2010-01-10T01:11:46.247-05:00

This is an interesting discussion no doubt, but it seems a little too analytical and not so much practical. The previous anonymous poster hit it right that the Pats coach has a feel for whats going on on the field better than anyone else. Analyzing data can be a useful tool when calculating percent success over all teams over decades of football. It does not, however necessarily relate to the given game being played as all teams are of different skill level from talent to play calling and certain teams are just going to flat out be better at converting than others. Some may be successful some of the time while others may never squeeze a win or points after a decision to go for it. So many more variables would affect a given decision to go or punt that it would be impossible for one to accurately calculate the chances of winning a game based on this generic quantitative analysis.

An issue of some interest might be play selection ...

2009-12-23T14:44:53.491-05:00

An issue of some interest might be play selection in go-for-it mode. It appears that most coaches want to dominate the other team, thus multiple straight-ahead runs is a common choice (and commonly leads to failure). The Broncos used to have good results from variations off an Elway bootleg. At the very least, it adds some deception for the next crack at the center of the line!

Anonymous...here is the problem w/ your argument. ...

2009-12-22T10:22:08.427-05:00

Anonymous...here is the problem w/ your argument. A punt is a guaranteed turnover. Its throwing the ball 40 yards downfield and a 100% chance of interception. If you go for it on 4th down you are limiting your chances to a turnover to 25% (according to your math) so what's your preference on any given play, a 100% chance of a turnover or a 25% chance of a turnover.

Here is the problem with this argument. The odds ...

2009-12-22T09:16:44.528-05:00

Here is the problem with this argument. The odds of making the first down on fourth and one or fourth or two are statistically good. That is great and seems to tell us that "going for it" is a good decision. However it is not a good decision when you are in your own territory at all. Even if you team has better fourth down efficiency than the average. Here is why. Let's say your team makes 75% of their 4th and 2s. A very high percentage. The other side of that is that there is a 25% chance of not making it or a TURNOVER. What are the odds on a turnover on any other play? A run with a decent running back? I believe that the average is somewhere around 1 fumble for every 40 carries. How about intercepts per pass attempt? For a good QB it is around 1 in 30. For a bad QB it is lower. Now I am a coach in the NFL and I have the ball on the 30 yard line and I am going to run a play that has a 25 to 45% chance of turning the ball over? Which is the bad decision? Punting the ball and giving the ball to the other team in their territory when the best team in the NFL has around a 30% chance of scoring a Touchdown in that situation or risking an extremely high turnover play and giving the same team a 40 to 50% chance of scoring a TD and a much higher chance of kicking a field goal. I think we can see why 90% of the time or higher NFL coaches make the desicion they make.

All that being said. I am not questioning Bill Belichek's call. He has a better feel for what his team is doing on the field than I have. He would win the game with a first down. How his line is blocking. How beat up the other D line is. How his backs are running. However in most cases coaches should and do opt to punt in this situation. The odds of a TURNOVER are too high.

How does this breakdown in the case of last nights...

2009-11-16T20:03:32.166-05:00

How does this breakdown in the case of last nights game? The model should include:

1. Home vs away team
2. Lead or trailing at the time and by how many points
3. Current field position
4. Time left in the game
What does the model look like and tell us then? You should also weight the QB rating for the offense, and in the case you don't make the 1st down, the other teams QB coming back at you to score. That likelihood would go up the deeper you are in your own territory of course.

Yes. Yes. Yes. -Belichick fan

2009-11-16T10:03:51.704-05:00

Yes. Yes. Yes.

-Belichick fan

Great trin of thought. I have never seen such a c...

2009-11-13T09:51:00.073-05:00

Great trin of thought. I have never seen such a complete analysis of points. What really struck me is the expected points from a safety. Really cool.

Happy - there's tons of info on the net about ...

2009-10-31T04:43:11.507-04:00

Happy - there's tons of info on the net about the TPC situation

Part of the reason it can be successful is that teams can try in unexpected scenarios

But there is another school of thought that suggests TPC should be reserved (+ or -) for the last six minutes. A team trailing by 14 on scoring a TD should go for two because if successful the game can be won on the tying TD with the PAT. If it fails, the game can still be tied with a TPC. This route gives the best chance of winning without the dreaded OT

Ultimately you can't argue with success. The ...

2009-10-10T13:19:36.514-04:00

Ultimately you can't argue with success. The coach may take some grief in the short run for an unconventional decision, but if their decisions have a firm basis in expectation value and increase the team's likliehood of winning the team will win more games.

That's when the coach gets to say "that's why I'm the coach and you're the fans." Not every coach has this level of confidence, but some do.

I'm curious if there are any teams with greater than 50% on 2-point conversions. Those teams should never kick an extra point in the first three quarters of a game.

Jason, of course you are probably nailing the reas...

2009-09-15T13:53:33.220-04:00

Jason, of course you are probably nailing the reason why coaches behave as they do. But I think you are missing a few things here.

IF a more aggressive 4th Down Approach has a higher expected utility, it will lead to more wins, which help your job security a lot more then a nice perception.

Also if you read media articles of the last fw years, you will notice that the climate has definitely changed. Coaches get more ofen critized for being to timid, and aggressive failures have ample defenders in the press by now. SO I think even from a social risk/reward standpoint the times are changingand th caches should too.

I'm excited to see where this is going!

2009-09-15T10:00:49.942-04:00

I'm excited to see where this is going!

Unfortunately, even if a coach knows the odds, goi...

2009-09-15T09:43:03.112-04:00

Unfortunately, even if a coach knows the odds, going for it on 4th down is high-risk/low-reward from a social standpoint -- i.e., what will fans/owners/players/media think if we make it (or punt) vs. what will they think if we miss it? If you make it or punt, nobody says anything. If you miss it, why did you go for it there, you idiot? While that shouldn't be the sole deciding factor for a coach, it can have an effect on his job security and will therefore almost certainly figure into his decision-making process.

I tend to think of editing the same way. Nobody notices and rewards good editing, but if I let a few sutble errors slip by in whats supposed to be a profesional text, I'm labeled as a poor editor.

(You probably looked at my first paragraph and didn't think there was anything special about it, but you looked at my second and probably figured I was an idiot. Obviously, there's no "risk" in editing properly, but it's the same general issue of perception. Nobody notices if you do the right thing but they all notice if you fail.)