Buy or Sell?

I've spent the last couple weeks looking into stats from the 2010 season to try and see if I could find anything that might point towards a surprising outcome next season so I could put it in a FanPost to have a record I could brag about later. And, sure enough, after staring at the numbers and thinking really hard (which also describes my test taking strategy), I decided which numbers were useful and which weren't, and then found some "irregularities" that may end up showing themselves next season.

The stats I'm going to use are almost exclusively "per-attempt". I find "total" stats useless, since they are more easily skewed by factors other than the ones you're trying to measure. For example, I could get a thousand yards rushing if some NFL team decided to sign me and give me 700 rushes. So, using conventional stats, I would be a pretty good football player, when the reality is much better show in the yards-per-rush stat, which would correctly show that I'm not a very good running back.

To measure a team's offense I use yards-per-play (Y/P), which is a much better indicator than total yards or total points because both of the latter can be heavily influenced by defense and special teams, while Y/P depends solely on how much better your offense is than the opposing team's defense. To break it down further I use yards-per-carry (YPC) for running and Net yards per attempt (NY/A) for passing. NY/A is similar to yards per attempt except that it includes sacks. Net yards is better than yards because it measures how good each pass play is, while yards measures how good each pass is. For defense, I use the same stats, but obviously for opponents.

A third area I consider is kind of a miscellaneous category I call "Mistakes", which consists of penalties, turnovers, and special teams. Unfortunately, I was unable to think of a good way to measure how good special teams are, so I decided to ignore them. I don't think it matters too much since the best special teams are pretty close to the worst (I think).

Using these three areas (offense, defense, mistakes), I'm convinced that you can form a complete picture of a team and see where they're good and where they're not. So, using these tools, I will try and predict which teams will exceed expectations and which will be wondering how it all could have gone so wrong. These are roughly in order of my confidence of my predictions. (I won't mention the Chiefs since I can, and probably will, do an entire post on them).

Sell: Atlanta Falcons

This will probably be controversial, but I am completely convinced that the Falcons are very, very overrated. This is not because I'm biased against them or anything, but simply because fact after fact kept pushing me towards that conclusion until I could no longer resist. There's so much wrong here that they will get a bulleted list.

  • Matt Ryan is vastly overrated. And by "vastly overrated" I don't mean that he's just average instead of really good like everybody thinks. I mean he's pretty terrible. As in Matt Cassel is not only better, but better by a significant amount. As I mentioned, I measure passing by NY/A, where Ryan gets 6.0 NY/A. This puts him at 21st in the NFL between Alex Smith and Chad Henne. The only thing that really saves is his interception percentage (int%) at 1.6%, which is exactly the same as Cassel's. Unfortunately, Cassel's 6.2 NY/A is good for 15th in the NFL. So, in short, Ryan is a poor man's Matt Cassel, which isn't a compliment.
  • Michael Turner is vastly overrated. He had 4.1 Y/A, which is 25th in the NFL (with more than 150 carries). He can't catch either, with only 12 receptions last years. The only thing he does well at all is block, but blocking alone doesn't qualify you as being a good running back.
  • Atlanta was outclassed on offense and defense last year. On offense, they were below average on Y/P (5.0, 26th in NFL), NY/A (5.9, 22nd in NFL), and Y/A (3.8, 28th in the NFL), and offense is supposed to be their strong point. On defense they were below average on Y/P (5.6, 25th in NFL) and Y/A (4.6, 26th in NFL). They managed to do above average defending the pass (6.1 NY/A, 17th in NFL), but only because the bad pass defenses were so bad that they drug the average down.
  • So how did they manage to win 13 games? Because they did really well in the mistakes category, which isn't a good thing. For example, they were 3rd in the NFL with a +14 turnover differential. Why is that a bad thing? Well, I punched some numbers, and this is what I got. To_medium


    The x-axis is turnover differential in 2009 and the y-axis is improvement or regression in number of wins from 2009 to 2010. In other words, what does a turnover differential one year tell you about the next year. And as you can see, higher turnover differentials mean fewer wins the next year, and the correlation is pretty good (an r^2 of .11 is not bad for something like this). By plugging in 14 into that little formula, we get that the Falcons should expect to win about 2 fewer games next year based on this factor alone.
  • As far as penalties, they were 1st in the NFL with 3.8 per game (1st as in they had the fewest) and 4th in opponents penalties with 7.2 per game (this time the 4th most). Now, not committing penalties yourself is pretty good, since that tends to repeat itself the next season (I ran the numbers comparing 2009 and 2010 and the r^2 was something like .25), but they are most likely going to have more penalties next year (simply because that number has nowhere to go but up). On the other hand, that opponents penalty number is very bad news. That number doesn't tend to repeat (the r^2 was something like .02) so they should expect it to go down next year.
  • They had a pretty easy schedule last year outside of their division (I'm not including division in this since they play those teams again next year, and their division doesn't look to be getting any worse). That is, they played the NFC West last year. Next year they're playing the NFC North which, as we should all know after considering our own schedule, is a much tougher division.

In short, the Falcons were terrible on offense and defense, but made up for it by committing few mistakes while allowing their opponents to self-destruct. Combine that with their TE aging and their only good draft pick filling a need they didn't really have (their #2 WR is much better than ours), and you have a team who is in for a disappointing season.

Buy: San Francisco 49ers

Remember last year when everybody told you the 49ers were going to walk away with their division because they were so much more talented than the rest of them? Well, it turns out those people had a point. The 49ers are like a reverse Falcons; they were about average on offense (5.3 Y/P, 18th in NFL) and solid on defense (5.1 Y/P, 9th in NFL). That should have easily been enough to win the division. They were ultimately done in by that Mistakes area (which, I should point out, is the most "random" of the three). They had a -1 turnover differential (15th in NFL), but really hurt themselves by being very undisciplined (7.0 penalties per game, 28th in NFL) and their opponents not giving them much help (6.1 penalties per game, 15th in NFL). With a new coach, they should be more disciplined, and should therefore walk away with the division. And also because the team I think most people will pick to win the division is, well...

Sell: St. Louis Rams

The Rams were simply not very good last year. They were below average on defense (5.3 Y/P, 17th in NFL) but among the worst on offense (4.6 Y/P, 30th in NFL). But while most people know they were bad last year. they think that Sam Bradford is the next Peyton Manning. It's possible, and Bradford will almost certainly improve next year, but he was just terrible last year. You know who had the worst NY/A last year? Well, Jimmy Clausen. But you know who had the second worst NY/A? That's right, Sam Bradford, with 5.2. The gap between Bradford and Derek Anderson (!!!) is 0.2 NY/A, which is the difference between the 14th best QB and the 26th. And, just to be clear, Anderson did better! 

The main reason I'm including the Rams though is because they were #1 in number of penalties committed by opponents (7.9 per game) by a fairly wide margin over the #2 team (Oakland with 7.3 per game). So, again, that is the stat that will almost certainly regress to the mean, so they probably won't be able to lean on that to help them win games like they did last year. Their only real hope is that Bradford improves, and I honestly think he can. I looked into them a bit, and I'm convinced that the problem wasn't that Bradford sucked, but that he had nobody to throw to. If we traded Chris Chambers to the Rams, he would be the best receiver on their team. To make it worse, they didn't really do much in the draft to help him out.

Buy: New York Giants

I was kind of surprised to see how good the Giants were last year. Then I thought about it for a bit, and realized I should really be more surprised that a New York team who won the Super Bowl a couple years ago isn't being talked up by the media. On offense they were really good (5.9 Y/P, 5th in NFL) and really good on defense (5.1 Y/P, 9th in NFL). In fact, in terms of Y/P, they were better than us on both offense and defense.

So what went wrong? Well, they had a -3 turnover differential, but mainly that epic collapse against the Eagles which, had they won, would have put them in the playoffs. I'm pretty convinced the Eagles will fall off next year (but I don't have any stats to back it up, so I didn't include them in this post), and if that happens the Giants should win that division pretty easily.


I could include more teams, but I'm only really confident about these. I might also buy the Chargers (which is built on the hopefully wrong assumption that Norv won't screw them up again) and sell the Eagles(since it seems like teams have figure out how to stop Vick), but I'm not too sure on those.

As far as the Chiefs go, if I were an outside observer I would have to say Sell by these numbers. Almost everything I said about the Falcons also applies to the Chiefs, just to a lesser degree. I'll expand on this in my season preview, if I ever get around to it.

This is a FanPost and does not necessarily reflect the views of Arrowhead Pride's writers or editors. It does reflect the views of this particular fan though, which is as important as the views of Arrowhead Pride writers or editors.

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