Tuesday, April 30, 2013

The Kangaroo Score

The Kangaroo Score was something I came up with while trying to identify NFL Draft prospects that could become successful pass rushers.  I have seen other people who have used a similar method, but mine still has the honor of having the goofiest name.  So, I win on that point.

The score largely comes from a prospect's vertical jump and their broad jump.  Of course, not all jumps are equal.  A player weighing 200 pounds with a 36 inch vertical jump, simply isn't showing the same power or explosiveness as a 250 pound guy with the same jump. My solution was to multiply a players weight by their jump,  find what the average result was, and the see how many standard deviations a player's score was from that average.  It's just a simple way of gauging a player's lower body power.  We can extrapolate from this a simple mass times velocity equals force view of things, with the jump being used as the measure of velocity, to estimate the amount of force a player could generate against his opponent.  So, basically, I look at players as human projectiles.

For some positions, like defensive tackle, this could be seen as a measure of the power that they are generating when the ball is snapped..  It's sort a general test of an athlete's quick twitch muscles, and their overall explosiveness.  For defensive tackles this measurement alone is more than adequate to identify prospects, but I'll generally refine things a bit further.  As you move outwards from the defensive tackle, and a player's mass decreases from defensive ends to linebackers, to safeties, and finally to cornerbacks, you start to see agility become more of a factor.  The way I see it, a player (at any position, but in this case a pass rusher), could either explode through or past his opponent, or try to evade/work around them.  So, as their mass decreases it becomes more important that the player's score in the agility drills (short shuttle and 3-cone)go up.  Ideally a player would do well in all these categories, but that is somewhat unusual.  Continuing with the human projectile idea, you could compare a guy with a high Kangaroo score to a depleted uranium round fired from a tank, while a guy who also has a good agility score is more like a heat seeking missile.  Hmm, this human projectile idea is sounding more and more idiotic with every word I type.

Sticking with defensive tackles for a minute, let me add this.  While this explosiveness might be all that you need for a nose tackle, who can satisfy a team's expectations by simply being fat and immovable, the more their agility score goes up the more likely they are to create at least some pressure on the quarterback.

Here are some noteworthy defensive tackles and what their scores look like:

Player              Kangaroo Score            Agility Score
Haloti Ngata         2.043                            -0.645
B.J. Raji               1.478                            -0.531
Jay Ratliff              0.821                            1.530
Ndamukong Suh   0.900                            1.227
Geno Atkins          0.793                            1.056

On the other hand we have these guys, most of whom were highly drafted, that are entering bozo/failure territory (at least for their draft position):

Player              Kangaroo Score              Agility Score
Terrence Cody      -1.242                            -1.864
Torell Troup          -0.481                            -0.158
Glenn Dorsey        -1.466                            -0.188
Kentwan Balmer   -0.245                            -0.451
Justin Harrell          0.041                             -0.343

In Justin Harrell's case people might argue that he failed because of constant injuries, but I suspect there was little upside there to begin with.

The bulk of the players fall somewhere between these two groups, so evaluating them becomes a bit trickier.  My point is simply to suggest that such risky and subjective speculation should probably be reserved for the later rounds of the draft, and that high draft picks should generally conform more towards players who actually proved to be worth a damn.

Just for shits and giggles, I thought I would also throw out this score, though technically he is a 3-4 defensive end:
Player             Kangaroo Score                 Agility Score
J.J.Watt                 1.473                               2.347

Hmm, J.J. Watt, how can you not love those numbers?

Since I will probably refer to the Kangaroo Score somewhat frequently, I should probably mention something for the sake of clarity.  The Kangaroo Score for a player at one position generally shouldn't be compared directly to a player at another position.  This is because the score is a measure of how much they deviate from their peers at a particular position.  So, a linebacker with a 1.250 score may look good, but if he was dropped into the defensive tackle pool, he would get crushed, and his score would be much lower.

There are some other factors, such as college production, that I think are good to toss into the mix, but for now I just wanted to present a little bit related to the actual value of the NFL Combine.  People often want to dismiss its usefulness, but there is some important information that comes from it.  Later on I will try to show how some of these things relate to other positions (hmm, this was initially supposed to be about pass rushing 3-4 outside linebackers, but I got sidetracked).

Here are some links to different player positions, that illustrate the effects of the Kangaroo Score:
3-4 Outside Linebackers and 4-3 Defensive Ends
Athleticism and the Offensive Line
Athleticism and the Offensive Line pt. 2  Compares traits of  late round successes to highly drafted busts
'Big' Wide Receivers - focuses on Aaron Mellette, but illustrates the point.
Running Backs - talks about how the Kangaroo Score relates to being a 'power' running back
Athleticism and the Defensive Tackle -Compares the athleticism of successful DTs to busts.

An introduction to my lunacy

For a number of years I have been part of a loathsome subculture known as "draft geeks", "draft-niks", or simply guys "with no life".  This circle of bottom dwelling football fans takes a peculiar interest in the annual NFL Draft, trying to prognosticate the future success or failure of athletes who are making the leap from the college level to the NFL.  More often than not, our hunches prove to be wrong, but when we are right we become insufferable boors to all of our friends, happily ruining their Sunday diversions with spreadsheets and analysis that nobody asked for. 

 At some point, I suspect, the game itself became less interesting to us than the machinations that go into constructing the team.  While more stout and virile men take pleasure in watching a middle linebacker decapitate a running back, we obsess over the meaning of a player's time in the 3-cone drill.  Some little boys dream of being quarterbacks, some dream of improving on the Lewin Career Forecast. If given the opportunity to choose between hanging out with the cheerleaders, or getting to run our fingers through Mel Kiper's shellacked locks of hair, our decision would be embarrassingly simple and foolish.   

Do we care if the home teams wins on Sunday?  Or are we more interested in seeing that sixth round pick wide receiver, from North by Northeast South Dakota State, exceed all expectations and become a mediocrity rather than an outright failure, thus proving our wisdom to our uninterested friends and family?  Well, I guess we can agree to disagree on what matters more.

This sort of devoted lunacy ends up crossing over at some point to join the analytics crowd.  Frankly, I still believe the word "analytics" is made up, but I'll try to ignore this for the moment.  I suppose "soulless bastards" just doesn't have the same ring to it (and wouldn't look as nice on a business card).  This circle of sad individuals goes beyond the simple talent evaluation game that is the draft, and focuses more on predicting outcomes for games and individuals, based on the questionable belief that numbers are good for something more than counting the number of illegitimate children Antonio Cromartie has spawned.

The "analytics" crowd, an appropriately anal group, is on a quest to destroy any magic or pleasure that exists in the world.  They don't want to hear any discussion of a player's heart, determination or moxie.  Those are merely the traits you ascribe to the slow and unathletic.  That player you love, the one with the slow time in the forty yard dash, and the weak vertical jump, he's what they would call an "outlier".  Outlier is the sophisticated way of saying "improbable success", and that is only if that player becomes a success.  Until that moment of unforeseen success, outliers are treated with contempt.  Wes Welker and Anquan Boldin are the anti-Christ in the eyes of the analytics crowd, and exist only to make otherwise smart people look stupid.  This may not seem like a terribly kind attitude to take towards two of the games more productive wide receivers, but how can we be expected to be fans of guys who throw such curve balls to all of our delicately crafted projections?  Don't they understand how long it takes to put together these spreadsheets and formulas that predicted their failure? 

Still, while these two related groups, the draft geeks and the analytics guys, can somewhat suck the life out of the room, the is a reason why their numbers and influence might be growing.  The sophistication and accuracy of their projections do seem to be improving to the point where I think they could probably better the efforts of most NFL general managers.  Some of these geeks are better than others.  Some of them still deserve a wedgie.  Almost all of them should be avoided on Sunday afternoon, when you just want to enjoy the game.  But their day is coming, much like it did in the world of baseball.  Hopefully it will all take place behind the scenes, so as not to annoy the mainstream audience who would rather not have their game ruined with scatter plots and regression analysis.  If nothing else, you can take comfort in the probability that these wise but annoying individuals still probably won't be able to get a date on Saturday night (though they would be too busy with their spreadsheets then anyway), and so they will probably be bred out of our society in the long run.  Until then, I'll be posting some thoughts related to these topics and awaiting my own wedgie.