Inside the Numbers: 2002 Defensive Player of the Year Put on your tuxes and your helmets, TSL'ers, we're here to award our Third Annual TechSideline.com Football Defensive Player of the Year Award. For the last three years, we have done a defensive performance calculation and awarded points to defensive players based on their defensive stats. This is strictly numbers-based performance, no opinion or subjective analysis allowed. Last year, based on these calculations, we awarded the first-ever TSL Defensive Player of the Year Award to Ben Taylor, for his performance in the 2001 season. And we retroactively awarded Ben the 2000 award as well. If you read TSL's football game analysis articles, then you're familiar with the concept. The idea of a defensive performance index is simple: award points for certain defensive plays (tackles, sacks, interceptions, etc.), multiply a player's stats by those point awards, and total them up. You can then rank the defensive players by total points, and for a different twist, you can divide their total points by the number of plays they were on the field to get a "points per play" statistic that truly measures a player's productivity. As with many of the "Inside the Numbers" things we do, we accumulate more and more data as the years go by, and we can compare historical data across multiple years. I'll say this: the defensive calculations say a lot about the 2002 defense and why it struggled so much. Read on to find out what the story is. If you're not a numbers person, and you want to jump straight to the results and commentary, then scroll down to the section titled "And Now, the Results." If you've got the time and the mind for it, then just keep reading, and we'll tell you all about how the calculations are done. The Data We need two sets of data: defensive statistics and plays from scrimmage. 1.) Defensive statistics were taken from hokiesportsinfo.com at the following address: http://www.hokiesportsinfo.com/football/stats/teamcume.html 2.) Number of plays from scrimmage and special teams plays were taken from the season-ending depth chart found on page 7 of the December 20, 2002 edition of "hokiesports.com the newspaper" (Vol, 20, No. 16). Note that statistics are for the regular season only and do not include the San Francisco Bowl. This required us to take the hokiesports.com cumulative stats from the 2002 season, which did include the bowl, and subtract the bowl stats out. The reason we did this was two-fold: (1) to make it more consistent with 2000 and 2001; and (2) because a season-ending depth chart, which included plays in the bowl game, was not available. Players Included in the Calculation The defensive statistics posted on the hokiesportsinfo.com web site also include special teams plays and tackles, and that complicates things. I took the list of players included in the "defensive stats" and eliminated all of the players who are not on the defensive two-deep roster. This got rid of the special-teamers like Jared Mazetta who appear in the defensive statistics because they have made plays on special teams. I also deleted defensive players who did not play more than 100 plays on defense. I wound up with the following 23 players, all of whom played more than 100 plays on defense in the 2002 season: DT: Jason Lallis, Kevin Lewis, Jonathan Lewis, Tim Sandidge, Jimmy Williams, Jason Murphy. Note that DE Darryl Tapp and LB Alex Markogiannakis, who both had 89 plays from scrimmage, just barely missed the cut. (Funny story: Tapp had 282 special teams plays, and next to that figure, in hokiesports the newspaper, it says "not a typo" in bold print.) Defensive Plays and the Points Awarded Here are the points awarded for the defensive plays included in the statistics:
Notes: 1.) Tackles are complicated and are calculated like this: when a player makes a tackle, he gets 1 point (assisted tackle) or 2 points (unassisted tackle). If it's a tackle for loss (TFL), he gets an additional 2 points, plus 0.2 points for every yard lost on the play. If the tackle for loss is a quarterback sack, it is calculated just like a TFL, but the player also gets 2 bonus points for the sack. 2.) Points for fumble return yardage are double what is awarded for interception return yardage because fumble recovery statistics typically include less return yardage than interceptions. Most fumbles are recovered on the ground, whereas most interceptions are made standing up with a chance to run. Fumble return yards should therefore be awarded points at a premium over INT return yards. How Special Teams Skew the Numbers The fact that special teams plays are included in the defensive statistics provided on hokiesportsinfo.com complicates things and skews the results in many ways. For example: 1.) There are not as many defensive "plays" available to a special teamer as there are to a scrimmage defender -- sacks, QB hurries, interceptions, etc. are not available in a special teams play, except for the rare instances where the opponent runs a trick play. 2.) Sometimes the special team plays are plays like kickoff returns or field goals, where making any type of defensive play is impossible. This means that a defender who plays a lot of plays on special teams is going to have his point totals dragged down by those special teams plays. On special teams, he can't make a sack or an interception, so on average, he gets fewer points from his special teams plays, no matter how good a special teams player he is. But on the other hand, the tackles he makes on special teams go into his point totals and help him out, versus a player like defensive tackle like Kevin Lewis, who only had seven plays on special teams all year. You can sum up the effect of playing on special teams thus: 1.) It increases a player's point totals by giving him more opportunities to make plays, most notably tackles. 2.) It decreases a player's "points per play" figure, because special teams plays don't provide as many opportunities to score points. I tried to compensate for item number two by dividing the number of special teams plays in half when calculating the "points per play" statistic. So points per play = total points / (scrimmage plays + special teams plays/2). You can argue that I should have divided by a larger number or even thrown the special teams plays out completely, but it was hard to figure out exactly what to do, and that's the step I took. And Now, the Results Given all that, let's throw those 23 players and their stats into a spreadsheet and see what comes up. The table that shows each player's statistics and their resulting point totals is too lengthy and cumbersome to print here, but it can be viewed as a web page or a Microsoft Excel spreadsheet (see the end of this article to find out how to download the data). Players Ranked by Total Points (TechSideline.com Defensive Player of the Year) Without further ado, here are the top ten point scorers:
TSL Defensive Player of the Year: Willie Pile Willie Pile earns his first-ever TSL Defensive Player of the Year Award, after finishing 2nd in 2000 and 3rd in 2001. Willie piled up a personal-best 289.3 points, beating out his 223 points in 2000 and his 231.1 in 2001. Though Willie benefited from a 13-game regular season (as did all players this year), his points-per-game average of 22.3 is better than his per-game averages for 2000 (20.3) and 2001 (21.0). Despite the 13 games and the high score, Willie did not beat Ben Taylor's record of 306.2 points, set in 2001. Down below Willie, we note the following interesting facts:
Players Ranked by Points-Per-Play And in the all-important points-per-play category, which is another measure -- and perhaps the truest measure -- of a defender's effectiveness on the field, here's how it shakes out (a score of 0.40 or higher indicates a very productive defensive player):
Things to note:
An Encouraging Note In reviewing these statistics, I noticed the following:
That, Hokie fans, is a good sign. Comparisons of the last Three Years We've got enough data from the last three seasons to list the top 10 players in total points and points per play from 2000-2002. Here they are:
That's a nice spread among all seasons under consideration: 3 players from the 2000 season, 3 from the 2001 season, and 4 from the 2002 season. But remember, the 2003 season had two extra games in it. So what happens when we go to the points-per-play statistic?
The Data To download the data in HTML (web page) format, go here: http://subscription.techsideline.com/tslpass/2003/2002defensivestats.htm The page at the above address lists the players from first to last in terms of total number of defensive "points" scored. To download an MS Excel 97 spreadsheet containing all of the data and formulas that I have used here, go here: http://subscription.techsideline.com/tslpass/2003/2002defensivestats.xls I hope the spreadsheet has no significant errors, and I hope you enjoyed yet another brain-bruising installment of "Inside the Numbers"! Related Articles: Inside the Numbers: 2000 Defensive Performance -- TSL Extra #5, 3/16/01 Inside the Numbers: 2001 Defensive
Performance -- TSL Extra #19, 5/22/02
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