It’s football season in America again. Hallelujah.
As bad as most prognosticators are about most things, football prognosticators are really bad. Go back and look at just about any group of experts’ predictions for the coming season and you’ll see that their success rate is lower than that of the average monkey with a dartboard.
But for anyone looking to vindicate their terrible predictions, help has arrived: this article by Bill Barnwell of FootballOutsiders.com. It is a great look at a long-overlooked topic: the importance of injury on a given football team’s win-loss record. Using a metric called History-Adjusted Games Lost, Barnwell gives us an empirical look at the impact of various injuries on a team and a variety of nuances. If you are at all interested in the topic, you should read the entire article, but here are a few of Barnwell’s important conclusions:
- “Injuries, or their absence, have a drastic effect on a team’s success.”
- “A superstar is worth about six to seven times as much as a reserve.”
- “Offensive injuries are more significant than defensive ones.”
- “Injuries to the starting halfback do not affect the running game.”
So how do these conclusions help the case of bad football prognosticators?
Because football injuries are mostly the result of bad luck. Yes, you could argue that better players get injured less because they’re better prepared, better conditioned, and less likely to be caught out of position. But my sense is that these arguments may hold truer in a sport like baseball or soccer than in football, which is a game of collisions. If you agree that injuries are mostly the result of luck, then you could argue that many predictions go astray because the predictors couldn’t foresee the bad luck coming — but that their picks are otherwise sound.
If you run a football team and buy Barnwell’s analysis, then you’d probably want to spend a lot more time thinking about how injuries affect your season. Statheads have long grumbled that football has been slow to embrace a Sabermetric approach to the game (see Bill James here, on baseball; see Mike Zarren here, on basketball). It seems that football executives and coaches haven’t yet been convinced that certain statistical analyses provide the appropriate value and insight. But I can see how the kind of insights on injury that Barnwell offers might start to turn that tide. Even if a particular injury is the result of nothing more than bad luck, there are still lots of questions to empirically explore, such as:
- What is the optimal approach for a coaching and training staff to minimize injuries?
- What is the proper tradeoff between having very good and more expensive backups (an insurance policy against key injuries) and splurging for superstar starters?
- What is the best way to assess how a player’s previous injuries hurt his future abilities?
C’mon, NFL owners. There are a lot of newly minted statisticians out there. Surely a few of them are football fans who’d probably work cheap for a chance to bring some injury science to your business.
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My sense is that NFL owners are attempting to take such an approach. One of my colleagues (I’m a faculty member in statistics department at a large university) was recently offered a lucrative job with a prominent NFL team. He turned the job down, but he did note that the NFL is (or at least has been) behind the curve in terms of data collection.
To make the sorts of assessments that have been made in baseball and basketball, you need individual-level data on every single play of every single game and not just what play was run, what type of defense was faced, how many yards for that play, etc. As you can imagine, this sort of data is very difficult to obtain (i.e., assessing how each player performed on each play). Moreover, far fewer games are played each season in football than in basketball or baseball, contributing to the dearth of data.
Teams have started to collect data, but I wonder if it will be awhile before we start to see dramatic effects from that data collection.
Actually injuries have remained a remarkably resistant problem in all sports. Assessing the injury questions you raise is something that all professional sports teams try to do. Since I follow the RS I know that they- (a) hired Bill James and other sabermetricians to assess these probabilities and make recommendations, (b) hired the trainer who had worked with Dr. James Andrews with extensive experience with baseball injuries and designed a specific arm strengthening program for each pitcher, and (c) frequently sign injured players to variable value deals so that the player and team share the costs and benefits of their recovery. Still the differences are so small and luck is so important that the years when they had the fewest players lost to injury- 2004 and 2007, they won the WS, while each time the year after there were key injuries (especially to the pitching staff) that prevented them from repeating.
I suspect that the answer is to get superstars at key positions then realize that if they stay healthy you can win a championship, and if they get injured you can’t. Shoot for getting those superstars under contract for a few years together, surround them with average to above-average players and hope that one of those years everybody stays healthy. Assuming that is that the goal is to win a championship in the sport, which may not be the case for every owner.
I played football in high school and have watched it closely since then.
Injuries basically happen when people get tired, so I think that being in great cardiovascular condition would be the best way to stay injury free.
When you get tired..
1. you stop moving your feet (biggest cause of lower extremity injuries)
2. you may let yourself get out of position
3. you will be taking hits, not absorbing them
I wonder if my thesis could be tested by tracking if injuries increase in frequency as the game wears on.
I think the person who figures out how to prevent offensive line injuries will be the most valuable to an organization – but a lot of those injures seem to be the ones where someone rolls over a leg in a funny, awkward position.
Dave,
Even at the college level, teams grade out the performance of every individual on every play. All that data stays internal to the team, and may not be even stored electronically.
dan,
As far as offensive line injuries go, note that every lineman in the college and pros now wears knee braces as prophylactics.
Also, football is a very situational sport, which makes data difficult to interpret. For example, giving up 8 yards on first or second down is never a good thing, but on 3rd and 15 it is totally acceptable.
Statistics for individuals are also difficult to interpret. A star defensive tackle may be double and triple teamed at various points throughout a game, which could enable a less talented player to make more plays.
I do agree that most teams would benefit from a more statistical approach to the game, but I don’t know how far you will get breaking it down to individual players and positions.
Has anyone done a study on the effects of drugs and or injuries to athletes and or birth defects in their children?
Could it be that steroids are making their mucles to large for their bone structure and thus causing injuries. Doesn’t it seem that a large portion of professional atheltes have kids with issues. More so than the general population? Or is this just not there and it’s the notoriety that make it seem that way???
Let’s not forget that in football, as compared to most sports other than boxing, injuies are frequently inflicted on purpose. The bigger the superstar, the more likely it is the opposing team wil be “out to get him”.