With the Scouting Combine wrapping up earlier this week, I had planned to use the running backs' 40-yard dash data to introduce some of you to a really useful metric developed last year by the guys at Football Outsiders known as Speed Score.

Well, they ended up beating me to the punch.

Nevertheless, their article helps me because now I don't have to go through all the Combine data and do the calculations myself.  And of course, I'll be tailoring the conclusions to a Dolphins' perspective.

So without further ado, let me introduce the 40-Yard Speed Score.

So many people drool over the numbers that players generate at the Scouting Combine every year, but no one really ever bothered to go back and check just how useful the different drills are when it comes to projecting success at the NFL level.

That is, until FO came along and whipped out their...calculators.

Thus far, they've been able to find strong correlations between certain statistics and the quarterback, wide receiver and running back positions.

We've talked before on this site about the WR numbers - that is, their height/BMI combinations.  And you may have run across the Lewin Career Forecast as well (not usually credited as such, but oh well, right?), when it comes to projecting QBs.  This study found that when it comes to QBs taken in the first two rounds of the Draft, only completion percentage and games started matter in terms of projecting their success in the NFL.

For running backs, FO found that of all the raw data compiled at the combine, the vertical jump and the 40-yard dash are the only numbers that bear a strong correlation to performance.  You might as well throw out the bench press, three-cone drill, and Wonderlic test because they are virtually useless.

However, while conducting their research, they invented a new metric which bears an even greater correlation to performance than the 40-yard dash itself, and this is the 40-Yard Speed Score.

Here is the formula for this metric: (WEIGHT * 200)/(40 TIME^4)

What the Speed Score does is more accurately reflect a player's true speed, by taking into account the body frame being propelled forward.  It's essentially a 40 time adjusted for weight and placed on a 100-point scale.

This metric helps to separate players like Brandon Jacobs (4.56 seconds, 267 lbs.) from Ahmad Bradshaw (4.55, 198 lbs.).  Even though they can both traverse 40-yards in the same time, Jacobs' speed is much more useful because of the power behind it.  That is the essence of Speed Score.  In general, any speed score below 100 is poor, while the greater one's score is over 100, the better.

So let's take a look at the Speed Scores for this year's running backs:

*Source (FO.com)

First off, let me say that I am against drafting running backs early, and while I am pretty content with Miami's running back situation right now, it's clear that after this season they may need to have a capable backup plan in place.  After all, some serious decisions will have to be made soon with regards to Ronnie Brown and Ricky Williams' futures with the team.

So if Miami does indeed intend to select a running back in this year's draft, who does Speed Score suggest as a potential late-round sleeper? (Note: Jalen Parmele put up a terrific Speed Score of 112.2 last season, which was one reason I was sorry to see him leave.)

Well, the pickings overall are slim.  This draft is really thin at RB it would seem, with only 7 players posting scores better than 100.

Chris Wells and Donald Brown are immediately out of the picture for Miami since they will be gone on the first day.  Andre Brown will also probably be gone by the fourth round.

Ian Johnson, Javarris Williams, Kory Sheets, and Cedric Peerman could all be worth a look in the later rounds.  Peerman is particularly intriguing because most draft "experts" predict him going in the sixth or seventh round or even not getting drafted at all.  But if one of those four guys is sitting there when Miami is picking in the seventh-round, I would not mind seeing them take one of them.

So that's speed score in a nutshell for you.  It's definitely the best number to keep in mind when thinking about running backs on draft day.  It's certainly not foolproof (Brian Westbrook only scored 91.71) but its predictive ability is far more hit than miss.

(For those of you interested, Ronnie Brown scored a tremendous 121.0.  Carnell Williams scored a 112.7, and Cedric Benson scored a 97.5.)