14 Jul 2009
by Bill Connelly
Regular Varsity Numbers readers have probably become familiar with some of the basic VN concepts, namely PPP (Points Per Play) and the "+". PPP is a measure of explosiveness--the amount of Equivalent Points (EqPts) averaged per play. The "+" number compares an offense's output to the output expected against a given defense, and vice versa. With the "+" number, 100 is average, anything above 100 is good, and anything below 100 is bad.
Is there any way to use these concepts to come up with a good rushing measure? Of course! Meet POE (Points Over Expected), the collegiate stepchild of DYAR. Whereas a rusher's PPP+ would compare his EqPts output to what would be expected, and is therefore great for measuring an offense's overall effectiveness, POE is cumulative. It is a comparison of a rusher's total EqPts to the Expected EqPt total, subtracting the latter from the former.
POE = EqPts - Expected EqPts.
Sheer durability and longevity are important characteristics in a rusher, so simply looking at PPP+ doesn't tell the whole story. A runner can come in as a change-of-pace back for 5-6 carries per game and put up a drastically high PPP+, but that doesn't mean he would put up those high rates over the course of a game or season. A runner posts a high POE by showing both a successful PPP+ level and the ability to carry the ball many times. Some (Florida's Jeffrey Demps, North Carolina's Greg Little) proved they could post high PPP+ numbers, while Michigan State's Javon Ringer (30 carries per game) proved he could be a workhorse, but the names at the top of the POE list did both.
Let's take a list at who the POE measure tells us were the best backs in college football last year.
|Top 25 College Rushers according to POE, 2008|
|4||Jonathan Dwyer||Georgia Tech||So.||93.6||57.1||164.1||+36.5||12|
|5||Kendall Hunter||Oklahoma State||So.||112.7||78.7||143.2||+34.0||6|
|9||Evan Royster||Penn State||So.||84.7||54.2||156.2||+30.5||24|
|23||Roddy Jones||Georgia Tech||Fr.||41.3||23.4||176.1||+17.8||84|
|25||Keith Toston||Oklahoma State||Jr.||50.2||33.8||148.8||+16.5||87|
|* Declared early for the NFL Draft|
The six running backs who received the most All-America attention last winter were Greene, Dwyer, Hunter, Moreno, Donald Brown, and Michigan State's Javon Ringer. Ringer was fourth in the country in rushing yards last year, but where did he stack up in POE? A whopping 137th, between Ball State backup Cory Sykes and Colorado backup Demetrius Sumler. Ringer's 390 carries merited a POE of -0.3, meaning an average college running back would have put up exactly what he did in 390 carries. While there is certainly skill (or at least good genes) involved in managing 30 carries per game without breaking down, it is unlikely that the skills Ringer possesses will in any way translate to pro success. (More about pro success in a bit.)
Who were some other backs ranking high in yards and low in POE?
Jeremiah Johnson was an outstanding running back for Oregon last season, but assuming LaGarrette Blount's disciplinary problems are in the past (he was suspended in February for not fulfilling team obligations, whatever that means, and he was reinstated for spring football), Oregon's rushing attack might actually get better in 2009, especially considering their quarterback situation is much more stable this year with the late-season emergence of quarterback Jeremiah Masoli. Blount did more with fewer carries than anybody else in the country, and he should get more carries and opportunities to prove himself to a national audience this year. Combined with Cal's Jahvid Best, it appears that the best running backs are in the Pac-10 this year.
Four teams had two players in the Top 25. Three of those teams -- Oregon, Oklahoma State, and Georgia Tech -- were somewhat predictable. The fourth, Alabama, probably was not. Freshman receiver Julio Jones, an offensive line led by Andre Smith, and a stellar defense overshadowed the efforts of Tide backs Glen Coffee and Mark Ingram, who combined for 2,111 rushing yards, 22 touchdowns, and a combined POE of +44.7.
(It should be also noted that offensive line play -- in the form of Line Yards, Line EqPts, or Line Yards+ -- were not taken into account with these rushing totals. Solid line play from Alabama and other schools obviously positively impacted the numbers seen here. When Varsity Numbers ranks backfield units in August, line play will be subtracted somewhat from the equation.)
Who are some backs that could emerge onto the list (or, in some cases, higher onto the list) in 2009? While it is correct to note that high PPP+ levels may not be maintained with more carries, here are 2008's top 10 rushers according to PPP+:
|Top 10 Returning Backs according to 2008 PPP+|
|2||Greg Little||North Carolina||198.2||39|
|5||Roddy Jones||Georgia Tech||176.1||23|
|10||Jonathan Dwyer||Georgia Tech||164.1||4|
While Glen Coffee was solid and productive, Alabama may not miss a beat in the backfield, as Mark Ingram and Roy Upchurch should make for a strong duo. Meanwhile, Florida is ridiculously loaded -- they lose Percy Harvin, but will replace him, in part, with two of the country's most explosive runners in Jeffrey Demps and Chris Rainey (both of whom were freshmen in 2008). On top of those two, third-stringer and USC-transfer Emmanuel Moody ranked a solid 23rd in PPP+.
Meanwhile, Michigan's backfield should improve with the return of Brandon Minor and, sadly, the transfer of Sam McGuffie, who produced one of the nation's worst POE totals: -11.3.
Speaking of which, out of morbid curiosity, who were the worst major conference running backs according to POE?
|Lowest-Ranked Major Conference Running Backs, 2008|
|262||Dwight Tardy||Washington State||-17.2|
|257||LaMark Brown||Kansas State||-14.3|
|252||Dimitri Nance||Arizona State||-12.8|
|244||Josh Haden||Boston College||-10.9|
|* Rank is according to their ranking among the 267 eligible (min: 50 carries) running backs.|
Rodney Stewart produced a respectable 622 yards (4.7 per carry) in an injury-plagued freshman year in Boulder, but most of his yards came against shady defenses. He produced 107 yards (5.1 per carry) against a usually-decent Florida State defense, but FSU ranked just 64th in Rushing Defense S&P+ in 2008. He also produced 166 yards (5.9) against West Virginia (114th), and 141 (4.9) against Kansas State (88th), and was basically shut down by everybody else.
Using the same methods, who were the top-ranked runners at the quarterback and wide receiver positions?
|Top 10 Rushing Quarterbacks according to POE, 2008|
|2||Julian Edelman||Kent State||Sr.||99.3||64.9||153.1||+34.4|
|8||Pat White||West Virginia||Sr.||67.7||47.8||141.6||+19.9|
Colin Kaepernick was far and away the most effective rushing quarterback in 2008. Combined with a strong backfield mate in Vai Taua (17th among RBs in POE) and the best play-fake this writer has ever seen, Kaepernick has some dangerous weapons at his disposal in 2009. If Nevada can find a decent receiver to replace the steady Marko Mitchell, the Wolf Pack could be scary. Under the great and highly-accomplished Chris Ault, they have never beaten a BCS conference team that finished the season with a winning record, but they will get a couple chances in 2009. They start the season at Notre Dame on September 5 and host Missouri on September 25 -- and both of these teams (spoiler alert!) are projected by Football Outsiders Almanac to have a winning record in 2009.
|Top 5 Rushing Receivers according to POE, 2008|
|2||James Rodgers||Oregon State||So.||30.0||13.8||217.2||+16.2|
|3||Dexter McCluster||Ole Miss||Jr.||45.5||31.5||144.3||+14.0|
|4||Phillip Livas||Louisiana Tech||So.||20.3||10.3||197.0||+10.0|
|5||Kyle Halderman||Air Force||So.||20.9||11.0||190.8||+10.0|
Missouri's Jeremy Maclin, now with the Philadelphia Eagles, produced a combined +15.8 POE in 2007 and 2008, but while Maclin was a more durable receiver, Percy Harvin (combined 2007 and 2008 POE: +57.5) was in a league of his own in terms of what he could produce at any given moment.
So the next question to ask about POE is whether or not a strong POE is a harbringer for NFL success (or, on the flipside, is a weak one a harbringer of doom)? Data is limited in this regard -- right now, the VN database is still dealing with only two full years of data, 2007-08 -- but it might be a worthy diversion to take a look at 2007 POE levels compared to 2008 NFL production. Below is a list of the 20 running backs drafted in the 2008 NFL Draft (not counting Jacob Hester and Peyton Hillis, who were drafted as fullbacks).
|2007 POE Rankings for the 20 RBs drafted in the 2008 NFL Draft|
|1||Felix Jones (22nd Pick)||Arkansas||82.9||45.4||182.7||+37.5||118 / 81.8%|
|2||Jamaal Charles (73rd)||Texas||114.7||77.5||148.1||+37.3||63 / 15.3%|
|3||Kevin Smith (64th)||Central Florida||182.9||148.2||123.4||+34.7||79 / -0.5%|
|4||Chris Johnson (24th)||East Carolina||103.4||73.7||140.3||+29.7||175 / 9.2%|
|5||Rashard Mendenhall (23rd)||Pittsburgh||106.1||80.1||132.4||+25.9||injured|
|8||Ray Rice (55th)||Rutgers||138.9||116.2||119.6||+22.7||25 / -2.5%|
|9||Jonathan Stewart (13th)||Oregon||102.6||79.9||128.4||+22.7||122 / 7.6%|
|14||Steve Slaton (89th)||West Virginia||82.6||64.4||128.3||+18.2||166 / 5.8%|
|24||Mike Hart (202nd)||Michigan||90.3||76.5||118.1||+13.8|
|36||Justin Forsett (233rd)||California||96.4||85.1||113.2||+11.3|
|37||Matt Forte (44th)||Tulane||140.3||129.0||108.7||+11.2||20 / -7.1%|
|39||Darren McFadden (4th)||Arkansas||116.0||104.9||110.6||+11.2||-2 / -8.9%|
|42||Thomas Brown (172nd)||Georgia||54.9||44.9||122.2||+10.0|
|45||Marcus Thomas (166th)||UTEP||78.8||69.2||113.9||+9.6|
|52||Allen Patrick (240th)||Oklahoma||61.0||51.9||117.6||+9.1|
|53||Jalen Parmele (176th)||Toledo||103.5||94.4||109.7||+9.1|
|54||Tashard Choice (122nd)||Georgia Tech||84.1||75.1||112.0||+9.0||157 / 32.0%|
|86||Chauncey Washington (213th)||USC||63.4||59.1||107.4||+4.3|
|88||Ryan Torain (139th)||Arizona State||36.7||32.9||111.6||+3.8|
|104||Cory Boyd (238th)||South Carolina||53.2||51.1||104.1||+2.1|
With such a small sampling of data, it would be foolish to reach any concrete conclusions here, but it is still worth noting that three of the top four rookies in terms of 2008 DVOA were among the top four seniors in terms of 2007 POE. Felix Jones had the best POE and was on his way to a stellar rookie season before injuring his hamstring, toe, etc.; meanwhile, Darren McFadden was ranked much lower in POE than in most regular statistics, and he finished with a disappointing rookie season. Clearly there is still a lot of work to be done in terms of analyzing POE and how it impacts pro performance, but... look out, Speed Score!
Most Varsity Numbers measures, in one way or another, bounce output versus expected output. POE, a brother to PPP and cousin to S&P and S&P+, does just that. POE, which intends to both evaluate both per-play and cumulative success, could also be used to evaluate receivers and tight ends, but that will be hard without good "pass intended for _____" data (some college play-by-plays record detailed information in this regard, others do not). Right now, it is an RB-only figure, but it is a pretty good one.
16 comments, Last at 16 Sep 2010, 6:16am by edwin.