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Creating a NFL draft value chart, Part I

by Chase Stuart on November 13, 2012

in Draft, Strategy, Team Building

Nearly five years ago, I came out with my own draft value chart to replace the “Jimmy Johnson” draft chart commonly cited by draftniks. What I did then was assign the career approximate value grade to each slot for each player drafted over a 30-year period, smoothed the data, and came up with a chart that actually represented career production.

The chart was due for an update in any event, but I’m going to make a key change. Using each player’s career AV makes sense on some level, as the drafting team gets the chance to have a player for his entire career. But the real value in the draft –especially now thanks to the new collective bargaining agreement — is the ability to get a player for cheap on his rookie contract, which expires after (at most) five years. The Jets got a great deal with Darrelle Revis early in his career, but now that he’s the highest paid cornerback in the NFL, much of his value (even pre-injury) is gone.

There’s also another consideration. Of the 100 top-ten draft picks between 1998 and 2007, only 48 players1 were still on the same team entering their sixth season. From the perspective of the head coach, things look even bleaker. In only eleven instances were the head coach and the top-ten pick still on the same team after five years (i.e., in year six): Chris McAlister and Jamal Lewis with Brian Bilick in Baltimore, Donovan McNabb with Andy Reid in Philadelphia, Richard Seymour with Bill Belichick in New England, Julius Peppers and Jordan Gross with John Fox in Carolina, Carson Palmer with Marvin Lewis in Cincinnati, Eli Manning with Tom Coughlin in New York, A.J. Hawk with Mike McCarty in Green Bay, Mario Williams with Gary Kubiak in Houston, and Levi Brown with Ken Whisenhunt in Arizona.

If you’re a head coach — or a general manager — I’m not sure it makes sense to project any more than five years down the line. Therefore, I’m going to construct my draft value chart based on the amount of Approximate Value provided by that player in his first five years after being drafted.2 Using PFR’s AV as my guide, I graded each player drafted from 1980 to 2007 and counted how much AV they accumulated in each of their first five years. Below is a chart plotting the data along with a smoothed line:



How does that compare to the NFL draft value chart? Before we can do that, we need to make one adjustment. The NFL draft value chart was designed to measure the marginal value of a pick or a player, while AV measures total value. In the draft, the last pick has only negligible value; however, even undrafted players would be expected to have accumulate some AV. So in order to to make the AV chart measure marginal value, I am going to subtract 3.6 points from each draft slot (that’s because the last slot is worth 3.7 points of AV). You can view these marginal values for the first 224 draft picks here.

In order to place the NFL draft value chart (which goes up to 3000 points) on the same graph as the AV value chart, I am going to measure each pick as a percentage of the total number of points given in each system. In the NFL draft value chart, the first pick is worth 3,000 points, while all 224 picks are worth a total of 60,684 points. As a result, the first pick counts for 4.9% of the entire draft value, compared to just 2.1% in this modified AV system:

As you can see, the charts look pretty different. According to the AV graph, the top picks are significantly overvalued relative to the middle round selections. It’s hard to know what’s “right” when designing a draft value chart, but the results here are pretty interesting. I agree with Brian Burke’s theory that draft picks are more like gladiators than bricklayers; there are only so many slots on a roster and so many starters, so you can’t simply look at value in a vacuum. I’m not sure the above chart would tell me to automatically trade down and get second and third round picks if I was running an NFL team. Still, it’s hard not to ignore how sharply the NFL draft value chart drops off, which doesn’t bear much resemblance to reality.

Before I move on to Part II, I’d like to hear your thoughts.

  1. counting Eli Manning and Philip Rivers as staying with the teams that drafted them []
  2. Note: I am giving the player credit for all of the AV he earned, regardless of whether or not it was accumulated with the team that selected him. []

{ 11 comments… read them below or add one }

Josh November 13, 2012 at 2:12 am

So, Round 4-7 is mostly junk?

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Chase Stuart November 13, 2012 at 11:26 am

Less so in the AV chart than the NFL one. Also, it’s worth keeping in mind that there is a bias in the data to the extent that teams play highly drafted players due solely to their draft status (and ignore late round picks for the same reason).

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Richie November 13, 2012 at 3:01 pm

I wonder if it would work for an NFL team to consistently trade out of the first and second rounds, to stock up on (cheaper) third and fourth round picks and give them legitimate opportunities to compete for roster spots, regardless of their draft positions.

Not sure if this would be related to this series of posts you are doing, but is there a way we (you) can estimate how many games played are wasted on high draft picks (such as Ryan Leaf) who aren’t worth it, and also how many low draft picks are not given a fair opportunity.

I’m thinking at an obvious QB outlier like Tom Brady. We know he is NFL-worthy. Would he have ever gotten a shot in New England if Bledsoe didn’t get hurt? If so, how much longer would he have sat on the bench before getting a chance? The rest of 2001? 3 more years? I count 35 QB’s who were drafted in the 5th-6th round between 2000 and 2007. 13 of them never attempted an NFL pass. (Suprisingly, 10 of them actually have 10,000+ career passing yards.) 5 of them have 16+ career starts. Marc Bulger and Tom Brady are the two who were obvious legitimate QBs. There are some borderline guys like Bruce Gradkowski, AJ Feeley, Dan Orlovsky and Derek Alexander.

So I guess my question is: can we use some statistical analysis to try to estimate if it is likely that the guys who actually started a handful of games are the only ones truly worthy of the opportunity?

A couple of these guys have some decent numbers (usually in good environments), but never had much opportunity. Craig Nall had a 123 QB rating in 48 attempts (0 interceptions). Jim Sorgi had a 6 TD’s against 1 career interception in 156 attempts.

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Richie November 13, 2012 at 3:28 pm

Sorry. I rambled again. Sometimes I wish there was a “Delete Post” button.

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Chase Stuart November 13, 2012 at 3:31 pm

Consistently might not be the word I would use. I think for a bad team, this makes sense, but for a good team, it would not. This is one of the reasons that I thought Belichick’s philosophy of trading down and stockpiling picks made little sense, and New England often ended up cutting players. For the Patriots, the odds of a 3rd round pick making an impact were much lower than for the Chiefs. NE should have been trading up to try to get impact players.

I think the first part of your question is a easy one to answer. I’m not sure about the second one.

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Richie November 13, 2012 at 3:57 pm

I’m not positive that Belichick’s philosophy didn’t work.

I have them as the 4th-best 10-year dynasty since the merger (after the 70s Cowboys, 70s Raiders and 80s-90s 49ers).
And they are also one of the best 15-year dynasties, despite only being good for 12 seasons.
And they are doing it during the free agency/salary cap era.

3 Super Bowl wins and 5 appearances in 12 years. Belichick has consistently had his team in Super Bowl contention for a decade+. How much better could he do? If he had been investing more in 1st round picks that busted and ruined his salary cap, he might have had to go through a rebuilding season or two along the way.

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DSMok1 November 13, 2012 at 9:33 am

Excellent, Chase. This is the same structure I used to create my NBA draft pick value system several years ago ( http://godismyjudgeok.com/DStats/APBRmetrics_Old/viewtopic.php@p=31637.html )

Next should be comparing that value to the price of the pick.

Ideally, one should use the overall price of AV in the NFL ($ per AV), and then subtract out the rookie contract slot to get the actual value of the pick (like I did for the NBA).

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Jon November 15, 2012 at 10:59 am

Hey Chase,

Does position have any impact on things? For instance are certain positions above the curve, while others are below it? Which would mean it would make more sense to pick certain ones early and others later

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Chase Stuart November 15, 2012 at 11:56 am

As you can see, without smoothing the data, the results can be a little choppy. If you start going by position, my guess is there will be too much noise to draw any real conclusions, but it’s worth considering.

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JeremyDe January 28, 2013 at 12:54 am

I just stumbled on this site yesterday. Previously, I read the pfr blog while it existed. Nothing major to contribute to this topic, although I do remember thinking along the same lines when I read the PFR post. Specifically thinking of limiting the AV to the first 3 years due to players leaving teams and because today’s coaches and GMs can’t expect to be somewhere more than 3 years or so.

I saw your 2nd footnote about calculating all AV connected to a player. Wondering how difficult it would be to eliminate AV that is associated with later teams, and if it changes the graph that much.

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Chase Stuart January 28, 2013 at 11:18 am

Thanks Jeremy. I plan to do some work on this in the off-season, perhaps addressing some of these concerns.

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