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He even has a calculator so you can now add incorrect statistical decision making His methodology is suspect. The entire premise (there have been similar reduc

He even has a calculator so you can now add incorrect statistical decision making His methodology is suspect. The entire premise (there have been similar reductionist statistical studies that holistically look at it as pure positional numbers) is founded on the notion of the weighted point value of each 1st down position. But as others have mentioned, on-fire offenses against miserable-defenses (e.g. New Orleans taking on Dallas) are going to absolutely dominate such a ranking, because they're of course going to dominate first downs (the survivorship bias -- the ones who suck go three and out), and they're more likely to be scoring points, completely throwing off such a weighting. If you're dominating a game but have a couple of missed passes, coaches often will go for fourth downs. If you're having little success, on the other hand, why give up good field position, and instead try to just push them back and hold them off until you can regroup. If Minnesota is 3rd and 4 at their own 35, they quite rightly -- and with full statistical backing -- aren't going to go for it if it isn't a desperate last minute drive. We of course have actual stats on the probability of making a fourth down- http://espn.go.com/nfl/statistics/team/_/stat/downs/sort/fourthDownConvPct http://espn.go.com/nfl/statistics/team/_/stat/downs/sort/fou... And the probability of blocking such an attempt- http://espn.go.com/nfl/statistics/team/_/stat/downs/sort/fourthDownConvPct/position/defense http://espn.go.com/nfl/statistics/team/_/stat/downs/sort/fou... Teams have a less than 50% chance of making it on average, though of course specific teams and specific opponents will completely throw off that count, and such is what weighs on the minds of coaches making these decisions, having to do so outside of "if we were an entirely average team against an entirely average team..."

tghw 13y ago
Teams have a less than 50% chance of making it on average Ultimately, that's not what matters. Expected value is what matters. Take the example from the video of a team on its own 5 yard line with 7 yards to go: If they go for it and don't make it, they leave the other team with the ball on the 5 yard line, which they will convert into a touchdown 92% of the time, an expected value of -6.44 points. If they punt, the TD conversion goes down to 77%, an expected value of -5.39 points. Therefore, the break even is about 16% 4th down conversion rate. If a team can make it more than 1 in 6 times, they should go for it instead of punting. Since most NFL teams are in the 40-50% range, they should be going for it more often.
- dragonwriter 13y ago
  > Take the example from the video of a team on its own 5 yard line with 7 yards to go: > If they go for it and don't make it, they leave the other team with the ball on the 5 yard line Actually, if they go for it and don't make it, they either leave the other team with the ball somewhere between the goal line and just short of the 12, or they end up giving up a safety (which has both score and possession effects.) Failing to convert on fourth down doesn't mean that you hand the ball over where you were before fourth down in the general case (only in the cases of an incomplete pass or zero-yard run, which aren't the only cases of failing to make a first down.)
- gfunk911 13y ago
  This is incorrect, because the scenario where they go for it and make it does not have a value of zero..it is still -EV
  - tghw 13y ago
    It's true, but I didn't have the data. Regardless, it decreases if they convert, which might double the break even point, but it still wouldn't be unreasonable.
- twoodfin 13y ago
  Are you claiming that most NFL teams gain 7+ yards on 40-50% of plays? That can't even be close to right.
  - mehwoot 13y ago
    There are 18 Quarterbacks in the NFL with an average Yards per Attempt over 7 yards. So it could be in the ballpark, at least.
    - jcampbell1 13y ago
      Average isn't relevant in this case. What you want is percent of Attempts over 7 yards (which is more akin to median). Four zero yard plays + Four five yard plays + two 25 yard plays = 7 yards per attempt, but a 20% success rate.

tghw 13y ago

Teams have a less than 50% chance of making it on average Ultimately, that's not what matters. Expected value is what matters. Take the example from the video of a team on its own 5 yard line with 7 yards to go: If they go for it and don't make it, they leave the other team with the ball on the 5 yard line, which they will convert into a touchdown 92% of the time, an expected value of -6.44 points. If they punt, the TD conversion goes down to 77%, an expected value of -5.39 points. Therefore, the break even is about 16% 4th down conversion rate. If a team can make it more than 1 in 6 times, they should go for it instead of punting. Since most NFL teams are in the 40-50% range, they should be going for it more often.

dragonwriter 13y ago
> Take the example from the video of a team on its own 5 yard line with 7 yards to go: > If they go for it and don't make it, they leave the other team with the ball on the 5 yard line Actually, if they go for it and don't make it, they either leave the other team with the ball somewhere between the goal line and just short of the 12, or they end up giving up a safety (which has both score and possession effects.) Failing to convert on fourth down doesn't mean that you hand the ball over where you were before fourth down in the general case (only in the cases of an incomplete pass or zero-yard run, which aren't the only cases of failing to make a first down.)
gfunk911 13y ago
This is incorrect, because the scenario where they go for it and make it does not have a value of zero..it is still -EV
- tghw 13y ago
  It's true, but I didn't have the data. Regardless, it decreases if they convert, which might double the break even point, but it still wouldn't be unreasonable.
twoodfin 13y ago
Are you claiming that most NFL teams gain 7+ yards on 40-50% of plays? That can't even be close to right.
- mehwoot 13y ago
  There are 18 Quarterbacks in the NFL with an average Yards per Attempt over 7 yards. So it could be in the ballpark, at least.
  - jcampbell1 13y ago
    Average isn't relevant in this case. What you want is percent of Attempts over 7 yards (which is more akin to median). Four zero yard plays + Four five yard plays + two 25 yard plays = 7 yards per attempt, but a 20% success rate.