## Tuesday, June 30, 2009

### Sun Belt SDPI

One of my favorite set of posts from the past two offseasons has been the SDPI recap/early preview. Don't know what SDPI is? It stands for Standard Deviation Power Index and is a tool Eddie Epstein used in his book Dominance to rate pro football's best teams. The basic idea is to look at how far above or below average (by standard deviations) a specific team is relative to their conference brethren. Since each team plays the same number of conference games, it can give us a good idea about who the best team was within the conference. However, it cannot tell us which conference is better. But the purpose of these posts is not to determine which conference is superior, but rather project ahead which teams in a conference will be contenders or also rans in the upcoming season. In the first post on SDPI two years ago, I calculated SDPI based on points scored and allowed within conference play. Last season I used points scored and allowed as well as yards gained and allowed. This season, I'm sticking with yards only. The yardage version of SDPI has a better correlation with future performance than points, and including both last season made the post seem (at least to me) quite muddled. Of course, this is by no means, the end all be all rating system, but it can give us an idea of which teams will improve and decline in 2009. This is our last stop on the SDPI train, wherein we will examine the youngest IA conference, the Sun Belt.

If you want the meat of the article, skip this next paragraph as it just gives an example of how SDPI is calculated. The mean yardage for and against for all Sun Belt teams in conference play was 2758.625 yards. The standard deviation for yards gained was 220.3. The standard deviation for yards allowed was 362.97. Florida International gained 2583 yards in conference play and allowed 2731. Their offensive SDPI was -0.80 = ([2583-2758.625]/220.3). Their defensive SDPI was 0.08 = ([2758.625-2731]/362.97). Their total SDPI was -0.72 which ranked 5th in the conference.

To refresh your memory, here are the 2008 Sun Belt Standings.

Now here are the 2008 SDPI Standings sorted by total SDPI, with conference rank in offense, defense, and total SDPI in parentheses.

The SDPI standings allign pretty well with the actual standings. Troy and Louisiana-Lafayette (now known as just Louisiana) were the cream of the crop, followed by Arkansas State and Florida Atlantic. North Texas was by far the worst team in the league.

Best Offense: Louisiana-Lafayette 1.81
The Ragin Cajuns had an eye-popping offensive game when they took on state rival Louisiana-Monroe. The Cajuns tabulated 728 total yards and averaged an unheard of 12.1 yards per play. Running back Tyrell Fenroy had nearly 300 yards on the ground (297), quarterback Michael Desormeaux added 149 yards rushing, and receiver Jason Cherry had 92 yards on just a pair of carries.

Worst Offense: Middle Tennessee State -1.49
Outside of an offensive showcase against the moribund defense of North Texas (489 total yards), the Blue Raiders averaged only 324 yards per game against their Sun Belt brethren.

Best Defense: Troy 1.41
No Sun Belt team gained more than 358 yards against the Trojans. The Trojans also proved their worth outside the league, holding Ohio State to 309 yards in Columbus and LSU to 340 in Baton Rouge.

Worst Defense: North Texas -1.59
Probably the worst defense in all the land last season. They did manage to hold Florida International to 347 yards in their best effort of the season, though they still gave up 42 points.

Looking ahead to next season, the prohibitive favorite should be...

Troy
The Trojans have either won outright or shared three consecutive Sun Belt titles, and they stand a good chance at making it four straight in 2008. The league's third ranked offense returns both a senior quarterback, Levi Brown, who took over in the sixth game last season and proceeded to throw 15 touchdowns against just three interceptions, and a running back who netted over 1000 yards on the ground, junior DuJuan Harris. Brown also has his top-target back, junior receiver Jerrel Jernigan, who paced the team with 868 yards last season. The offense should improve upon last season's performance. As a Troy fan, the only concern I would have for the offense is that other teams may leapfrog them. Troy was third in the conference in offense last season, but they only averaged about 11 yards more per conference game than the sixth ranked team (North Texas). Troy was good offensively, but their margin over the other Sun Belt teams is not exceptionally large. At least on offense. On defense, Troy was head and shoulders above everyone in the Sun Belt last season. However, that unit does lose six starters, and in particular, three from a secondary that was 29th in the nation in pass defense and 18th in pass efficiency defense. That side of the ball may experience some growing pains, especially considering the Trojans open with three of their first four games on the road. Troy is as good a bet as anyone to win the Sun Belt, but this is not Boise State we're talking about. It won't be a cakewalk.

The team(s) you should be buying are...

North Texas
The Mean Green suffered through an embarrassing 1-11 year in 2008, including a winless Sun Belt campaign. Their lone victory was against Western Kentucky (Sun Belt member starting this season). North Texas was quite pathetic last season (easily the worst team in the conference), but there is reason to expect improvement. For starters, the Mean Green boasted (?) a turnover margin of -17 (117th in the nation) and -13 in league play (last). The primary reason for the poor turnover margin was the 17 interceptions they threw (102nd in the nation) and the fact that they lost two-thirds of their own fumbles (16 of 24). This is the third year of head coach Todd Dodge's spread offense, so the quarterback (likely Dodge's son Riley) should be playing with a more knowledgeable cast, and the interceptions should drop. North Texas should also have better luck falling on their own fumbles, so their turnover margin should improve. The defense, statistically the worst in the nation last season in both yards and points allowed, returns nine starters, including the top seven tacklers, so its virtually impossible for that unit not to improve slightly. North Texas won't go bowling in 2008, but they have a realistic shot of matching their win total in coach Dodge's first two seasons combined (3).

The team(s) you should be selling are...

Louisiana-Lafayette
If the Ragin Cajuns were going to find their way to the first bowl game in school history, last year was the year. A senior quarterback, running back, and wide receiver powered the Cajuns offense to the best mark in the conference. They even challenged BCS-member schools Illinois and Kansas State on the road, before losing by 3 and 8 respectively. The Cajuns did finish second in the conference and were bowl eligible for the third time in four seasons. However, Florida Atlantic was the second Sun Belt team selected for a bowl game, and the Cajuns had to spend the holidays at home. Now those three skill players are gone, and despite the fact that seven other starters return, including all five along the offensive line, it appears as if the offense will decline. The defense, far from a strength last season (sixth in the league), does return 9 starters, so they should see some improvement on that end. The Cajuns have been very competitive under head coach Ricky Bustle, and they may even flirt with bowl eligibility this season, but expecting them to match their five league wins from last season is foolhardy.

The team(s) you should be holding are...

Arkansas State and Western Kentucky