SB Nation User Blog: abender20

Goodell and Mora Reach Summit

abender20 — Thu, 09 Jul 2009 15:14:59 -0000

Assessing the Accuracy of WP

abender20 — Wed, 08 Jul 2009 15:24:22 -0000

Between John and I, there have been a couple of posts at FG related to the Advanced NFL Stats Win Probability charts. If you've paid any attention, you know just how neat they are. If you are a generally curious person, you probably have wondered about the accuracy of the WP charts. Wonder no more. If you have no interest in probabilistic models, you should probably just stare at a wall for a few minutes.

For readers who are accustomed to linear regression models, you'd expect to see a goodness-of-fit statistic known as r-squared. And for those familiar with logistic models, you'd expect to see some other measure, such as the percent of cases predicted correctly. But the win probability model I've built is a complex custom-built model, using multiple smoothing and estimation methods. There isn't a handy goodness-of-fit statistic to cite.

We can still test how accurate the model is by measuring the proportion of observations that correctly favor the ultimate winner. For example, if model says the home team has a 0.80 WP, and they go on to win, then the model would be "correct."

But it's not that simple. I don't want the model to be correct 100% of the time when it says a team has a 0.80 WP. I want it to be wrong sometimes. Specifically, in this case I'd want it to be wrong 20% of the time. If so, that's a good feature of any probability model. This is what's known as model calibration.

Right, so that's it for the wall of text. If you are still reading, now go check out the charts in the article. The first shows a very nice relationship between actual results and the predicted results. There's a problem, however: The top chart shows the relationship between the 2000-2007 data and the model, which was built off of the 2000-2007 data. When building and subsequently testing a model, it's important to split the data into what's known as test and training data sets, part of the cross-validation process. If you test a model with the same data you created it with, the results will almost certainly show a very good model*. To ensure that this wasn't the case, Burke tested his model against the 2008 data, and the results look pretty good for a single-season sample.

Also, Burke charted out the model confidence, which is pretty interesting to look at from a fan perspective. It makes sense that the average game should start out with a roughly 50/50 split at kickoff. As late as the ten minutes from the end, however, there is generally only about ~80% confidence in a winner. That leaves a lot up for grabs.

*Unless you screwed up.

Still Unsigned

abender20 — Mon, 06 Jul 2009 15:51:25 -0000

It's not easy to keep track of every single roster move by every team in the NFL, especially when your vested interest lies with one team. That's why I was somewhat surprised when I saw this list of free agents from Jason La Canfora's blog. Pretty impressive set of names, isn't it?

It's not surprising why several of those guys have not been signed. Edgerrin is on the wrong side of 30 and showed his age last season. Shaun Alexander. Marvin Harrison has the combination of age, injury, and some mysterious allegations following him. Mark Tauscher tore a knee ligament in week 13 last year and comes in at age 32. I was a sophomore in high school when Willie McGinest turned 30. DeWayne Robertson can't even keep a website running:

At this point, pretty much anyone on this [list] is looking at a one-year, veteran-minimum-type deal, so it’s not a tremendous investment, and a lot of teams have ample space after the salary cap jumped this offseason.

With injuries such a part of the game, most teams will be looking for free-agent help by the first few weeks of August, with two-a-days chipping away at their rosters by then, and these guys are worth watching.

Barring a bunch of injuries, these guys won't be Seahawks. However, some teams will be desperate enough or at least willing to take a chance in signing some of these fellas. It's amazing how quickly NFL players go from stardom to the unemployment list.

Five Year Salary Numbers

abender20 — Fri, 03 Jul 2009 03:42:40 -0000

Here's a quick hit and run, as I left for SF several hours before this piece automatically published. Being the magnanimous soul that I am, I didn't want to leave you without something to read just because I'm getting further from my computer with every word you read. Danny O'Neil brings you aggregate payroll over the last five years. This isn't much other than the knowledge that Paul Allen is not pinching pennies with the Hawks, as we already learned that payroll doesn't correlate with winning. That's a lot of money.

Friday discussion question: If you could attend one and only one Seahawks game this year, which one would it be? Play nice and don't insult any mothers.

The Yellow Line

abender20 — Thu, 02 Jul 2009 15:16:53 -0000

Let's try a little game. I'm going to pose a series of three questions, and you will answer them one by one in your head. Don't follow the link until you've answered all three.

In your head, picture a football game. The offense has the ball and is about to pass. Don't consider YAC, but only the position of the catch itself relative to the first down line.

1.) It's third down. Where, relative to the televised yellow first down line and within +/- 2 yards of the line, is the most difficult distance to complete a pass to? I'm looking for a distance from the first down line, so horizontal distance from the quarterback is irrelevant at this moment.

2.) It's second down. Same question.

3.) First down. Again.

The answers can be found here.

How did you do?

See the Seahawks for Free

abender20 — Wed, 01 Jul 2009 15:14:35 -0000

at training camp. Well, sort of free. Transportation to and from the facilities will cost $5 a head. Details courtesy of the PI.

The team announced Tuesday that fans can attend practices at the Seahawks' waterfront headquarters on Lake Washington beginning on Aug. 3 and ending Aug. 20. They must first register through the team's Web site, seahawks.com, on a first-come, first-served basis beginning July 16 at 10 a.m.

This will be the first time since the team returned camp to the Seattle suburbs from Cheney, Wash., in 2007 that fans can watch the Seahawks practice.

The team will also hold two practices at UW in August.

If you've never been to a training and have a moment or two to spare in August, I recommend going. Firstly, you'll have the chance to see the new facilities in person, and the grounds are supposed to be fantastic. You may also enjoy watching Seahawk players in action and in person, both of which are pretty neat. A few summers ago, some friends and I drove up to Green Bay to catch a Packers training camp, figuring we'd get a chance to see Favre in action in what would likely be his last season. We were half right. Even though I am not in any way a fan of the Packers, I enjoyed watching NFL players go through a practice fifty feet away from where I was sitting. Watching a game on TV or even from up in the stands leads to a bit of a disconnect, in that you really don't appreciate just how incredible NFL athletes truly are. Kabeer Gbaja-Biamila, while on the smaller side for a defensive end, was huge. Ahman Green was jacked beyond belief. Even more impressive is the level of talent. Watch players you've only barely heard of perform amazing feats and still not make the roster. So again, if you have $5 and a day in August, go to training camp.

Carlson on 2009

abender20 — Tue, 30 Jun 2009 14:17:19 -0000

While rarely informative, I always enjoy hearing athletes talk*. While some of that stems from the entertainment value inherent in watching someone like Chris "Birdman" Anderson try to deliver holiday greetings (or Brandon Jennings running his mouth), these opportunities give you a better idea of the person in question. John Carlson took three minutes out of his life to talk to ESPN, and I think you'll enjoy hearing what he has to say. The content is fairly standard, but then again you shouldn't expect to learn Seahawks football strategy from one of these blurbs. More than anything, it's a chance to learn that John Carlson sounds like (sample size: three minutes) a well-grounded and intelligent young man.

* The notabe exception being on-court postgame interviews. Even the most well-spoken athletes (Tim Duncan comes to mind) just refuse to give any information away despite the labored insistence of the reporter.It's like watching a methed-up Quebecois try to bleed maple syrup from a spruce tree.

Over and Under

abender20 — Mon, 29 Jun 2009 15:35:09 -0000

I'll keep it brief as I'm limited on time this morning. Football Outsiders (Aaron Schatz, specifically) assembled a list of the 25 most overrated and 25 most underrated players of the last decade. Thanks to ESPN snapping up FO, you'll need to be an Insider to view all 25 and the explanations, but the top 10 from each group are listed. Any surprises on that list for you? It warms my heart to see the Halls (Dante and DeAngelo) sharing adjoining suites in the top 10.

If we were to compile a list of the most overrated and most underrated Seahawks in the last decade, who deserves a mention?

When Should You Hold?

abender20 — Thu, 25 Jun 2009 15:15:21 -0000

More photos » by Elaine Thompson - AP

"Hmm, Dockett gets to the QB 44% of the time he beats his lineman. This referee has been a little slow to notice my hand placement, and Dockett already has his shoulder by me. The coordinates of the corresponding point are then below a line with slope .81, so I'd better grab that mofo. Why is Matt on the ground holding his knee?" (AP Photo/Elaine Thompson)

Browse more photos »

Probability is neat. Brian Burke, the wizard behind the Advanced NFL Stats studies, strikes again. If you don't know the drill by now (follow the link!), you probably voted "13-14" on the poll yesterday. Also, you should stay away from sharp objects.

Using conditional probabilities based on first quarter game data, Burke shows that holding is actually an advantageous strategy more often than you'd think. The math involved is pretty straightforward, so go read. This boils down to game theory that can't possibly be used in a game situation as the odds of holding detection are not known aquantity. Holding detection involves all sorts of factors, like the egregiousness of the hold and the visibility of the interaction to the corresponding referee. Still, it makes an interesting case study. If you assume that getting beat results in a sack even 30% of the time, it's only worth holding if you the ref will blow the whistle 25% of the time or less. Bump p(sack | beat) up to 50% and you'd still have to hope the ref swallows his whistle on all but 40% of holds. Now assume your quarterback enjoys holding the ball and DeMarcus Ware is currently on his way by you (let's be honest, you aren't stopping Ware). Take him down.

How Many Wins?

abender20 — Wed, 24 Jun 2009 15:13:02 -0000

It's too early in the offseason to have a serious go at looking at schedules in the attempt to figure out how many games the Seahawks can expect to realistically win. Sure, part of that is the general uncertainty with respect to NFL teams, but the Hawks have way too many moving parts to know what to expect in the upcoming season. It's pretty easy to envision scenarios in which the Hawks win as few as five games or as many as 10-11 (that's where the poll comes in). A piece at the SF Examiner got me thinking about parity; what is a realistic expectation for how many wins it will take to take the NFC West?

Completely ignoring games outside of the division, it's fair to expect some better competition within the West. The Rams, 49ers, and Seahawks were all in the bottom 8 in Weighted Team DVOA last year. That's bad. The Cardinals? Only the 20th best DVOA. That's a bad division. With even some minor progress by the 49ers and Rams, win expectations decrease for both the Seahawks and the Cardinals. For the sake of argument, let's say it takes 9.5 wins to make the playoffs out of the West.

Poll

What is a realistic expectation for the number games won by the Seahawks in 2009?

3-4 (Injuries and age lead to disaster)

10 votes

5-6

32 votes

7-8

225 votes

9-10 (Probably a playoff team)

773 votes

11-12 (Mighty optimistic, aren't you?)

196 votes

13-14 (You hold conversations when you are the only person in the room)

41 votes

1277 votes | Poll has closed