The Football Power Index (FPI) Ratings are courtesy of ESPN
All other statistics are courtesy of Football Outsiders, home of the F/+ Combined Ratings for college football.
The Fremeau Efficiency Index (FEI) was created by Brian Fremeau; check out his website BCFToys for other goodies.
The S&P+ rating was created by Bill Connelly; check out his college football analytics blog, Football Study Hall.
Hat tips to Addicted to Quack's kalon and FO's 7th Day Adventure column for the inspiration.
So how’d last week go?
Yeah. Pretty much that, plus exploitation of how difficult it is to officiate college football and divine intervention for Mississippi. I don’t know either.
Hey, something new!
Bill Connelly is a crazy person. Evidently, he took a step back from the spreadsheets, assessed the splendor of content he produces on a daily basis for FootballOutsiders, SBNation, Football Study Hall, and Rock M Nation, and determined that wouldn’t do.
So, now we have Advanced Stats Profiles for all 128 teams in FBS, which will be updated weekly throughout the 2015 season. That link directs you to the index, which is ranked by current S&P+ ranking. The Alabama page is here. Both links will appear here each week moving forward, but they are static, so feel free to bookmark them if you so desire.
This is really awesome. Now you can say to yourself “Hey, I wonder what FIU’s success rate is on passing downs?” or “Which directional Michigan has the best IsoPPP?” and actually find that out, in a reasonable amount of time. This is amazing.
1 | You don’t ask these questions? It’s just me? Na, I’m pretty sure it’s everybody.
I will note that there is some commonality of information between Alabama’s Advanced Stats Profile and what you see every week in Charting the Tide, but you’ll find that the numbers may be slightly different. There are several reasons for this:
We use different data sources
Bill is kind of a big deal, whereas I am just some guy riding on his (and others') coattails. As such, he has access to the college football play-by-play data megatrove over at SportSource Analytics, which boasts an impressive resume of customers, including the College Football Playoff. The charting templates from the Charting Project come from this source, but those are usually not ready until Tuesday or thereabouts. For Charting the Tide, I cobble the basic play-by-play data together from RollTide.com and usually ESPN, which I use as a sort of guide for the charting process as well as the framework for defining the various splits you see in Charting the Tide. Theoretically this should all be the same data, but I do not know that for sure. Stuff like down, distance, etc. should be identical, but I frequently find errors in ESPN’s stuff in terms of player targets, ballcarriers, etc., that presumably shows up in the SportSource data as well. Just something to keep in mind.
We use different point models
This specifically affects IsoPPP values, which are based on Bill’s Net Equivalent Points model. To my knowledge, Bill’s never published the actual yard line/point value breakdown (he did for its predecessor, Equivalent Points), only a plotted curve in a Varsity Numbers column from a while back. I extracted the point values off this chart in order to calculate IsoPPP splits, with all of the error that entails. Why didn’t I just ask for it? Well, I had nothing to do at work one day, and as I typically find the bottom of the Internet by 9 AM or so, I had to find something to fill the rest of my time. The differences are small, so it’s not a big deal.
We calculate certain things differently
Namely, Opportunity Rate, which is defined as the rate at which a back turns carries into Highlight Opportunities (any run of five yards or more in length). Bill uses the total number of carries for his formula. The formula I use adjusts for runs inside the five yard line, such that a back is not penalized for not accruing five yards on a run where that’s physically impossible to accomplish.
Everything in the Advanced Stats Profile comes from the basic play-by-play data
That’s a ton of great stuff, some of which you won’t find in Charting the Tide. But there’s a lot more you find in Charting the Tide that you won’t find in the Advanced Stats Profile, which you can read about here. I’ll step down from the pulpit now and get to what you’re here for, but keep reading Processing the Numbers and Charting the Tide, start checking out the Advanced Stats Profiles, spay and neuter your pets, eat your vitamins...
Aren’t you supposed to be previewing something, nerd?
Right! The Alabama Crimson Tide look to avenge one of the worst losses in program history when they welcome the ULM Warhawks to Bryant-Denny Stadium. The game is on Saturday, September 26th, at 3 PM CDT / 4 PM EDT, and will be televised on the SEC Network.
|F/+||71.8% (1)||F/+||-27.2% (104)||ALABAMA|
|FEI||0.285 (1)||FEI||-0.11 (101)||ALABAMA|
|FPI||24.5 (4)||FPI||-7.4 (97)||ALABAMA|
|S&P+||32.8 (1)||S&P+||-10.4 (103)||ALABAMA|
|OS&P+||44.3 (6)||DS&P+||35.7 (103)||ALABAMA|
|Rush OS&P+||142.1 (6)||Rush DS&P+||91.7 (97)||ALABAMA|
|Pass OS&P+||138.7 (12)||Pass DS&P+||109.3 (49)||ALABAMA|
|SD OS&P+||145.4 (8)||SD DS&P+||83.6 (112)||ALABAMA|
|PD OS&P+||114.0 (53)||PD DS&P+||114.3 (49)||PUSH|
|DS&P+||11.5 (6)||OS&P+||25.3 (90)||ALABAMA|
|Rush DS&P+||190.5 (3)||Rush OS&P+||105.4 (67)||ALABAMA|
|Pass DS&P+||142.6 (10)||Pass OS&P+||143.6 (8)||PUSH|
|SD DS&P+||169.9 (5)||SD OS&P+||141.6 (10)||PUSH|
|PD DS&P+||131.0 (26)||PD OS&P+||116.9 (51)||ALABAMA|
(Bold) numbers indicate national ranking.
Statistics current as of September 23rd, 2015.
F/+: The F/+ combined ratings combine FEI and S&P+ into one metric that serves as Football Outsiders' official rankings for college football. For a more detailed discussion of F/+, check out this section of the PTN Football Primer.
FPI: The Football Power Index, an overall team quality metric produced by ESPN. Presented as a scoring margin, FPI weights factors such as offensive, defensive, and special teams efficiencies, as well as turnovers and big plays, and also includes opponent adjustments.
FEI: The Fremeau Efficiency Index, an overall team quality metric that is drive-based and opponent-adjusted. For a more detailed discussion of FEI, check out this section of the PTN Football Primer.
S&P+: Another overall quality metric constructed primarily from a play-by-play perspective, the S&P+ rating underwent big changes prior to the 2015 season. Check out the primer article for more details.
Off. F/+: The offensive component of F/+.
OFEI: The offensive component of FEI.
OS&P+: The offensive component of S&P+.
Rush OS&P+: S&P+ calculated on rushing plays for the offense — a good measure of a team's effectiveness at running the ball.
Pass OS&P+: S&P+ calculated on passing plays for the offense — a good measure of a team's effectiveness at throwing the ball.
PD: Passing Downs, defined as later downs with medium yardage or more to go (3rd, 4th downs in excess of 5 yards to go), as well as 2nd down with more than 8 yards to go.
SD: Standard Downs, defined as all downs that are not Passing Downs.
SD OS&P+: S&P+ calculated on standard downs for the offense — a good measure of a team's offensive effectiveness on earlier downs and short yardage.
PD OS&P+: S&P+ calculated on passing downs for the offense — a good measure of a team's offensive effectiveness on later downs and long yardage.
Def. F/+: The defensive component of F/+.
DFEI: The defensive component of FEI.
DS&P+: The defensive component of S&P+.
Rush DS&P+: S&P+ calculated on rushing plays for the defense — a good measure of a team's effectiveness at stopping the run.
Pass DS&P+: S&P+ calculated on passing plays for the defense — a good measure of a team's effectiveness at defending the pass.
SD DS&P+: S&P+ calculated on standard downs for the defense — a good measure of a team's defensive effectiveness on earlier downs and short yardage.
PD DS&P+: S&P+ calculated on passing downs for the defense — a good measure of a team's defensive effectiveness on later downs and long yardage.
Special Teams Metrics
FPA: FEI Field Position Advantage, a measure of how much field position value a team earned against its opponents.Fremeau Special Teams Efficiency Components - The special teams component of F/+ is based on Brian Fremeau’s Special Teams Efficiency, which is made up of the following five components of special teams play (per FootballOutsiders):
FGE — Field Goal Efficiency, the scoring value per field goal attempt earned by the field goal unit as measured against national success rates.
PRE — Punt Return Efficiency, the scoring value per opponent punt earned by the receiving team as measured against national return rates.
KRE — Kickoff Return Efficiency, the scoring value per opponent kickoff earned by the receiving team as measured against national return rates.
PE — Punt Efficiency, the scoring value per punt earned by the opponent's receiving team as measured against national return rates.
KE — Kickoff Efficiency, the scoring value per kickoff earned by the opponent's receiving team as measured against national return rates.
ASR — Adjusted Sack Rate, which is a version of sack rate (defined as sacks / [sacks + passing attempts] ) that has been opponent-adjusted. The metric is scaled based on an average rate of 100; the higher the rate the better. ASR is calculated for both the offense (OASR) and defense (DASR).
ALY — Adjusted Line Yards, which is a measure of success in the running game specific to the line. This is accomplished by taking each carry by running backs only and weighting the yardage as follows:
- Runs for a loss are weighted 120%.
- Runs for 0-4 yards are unweighted.
- Runs for 5-10 yards are weighted 50%.
- Runs for 11 or more yards are not included.
After the weighting process, the runs are further adjusted for game situation and opponent, and then averaged out per carry, resulting in adjusted line yards — a more detailed explanation of the entire process is available here. ALY is calculated for both the offensive line (OASR) and the defensive front seven (DASR).
The Swanson Giddiness Index
Easily the most accurate predictor of success in college football, the Swanson Giddiness Index is a qualitative, completely unsupportable metric that is presented via the tone of that week's image/animated gif of Ron Swanson — beloved Parks and Recreation character and official spirit animal of Processing the Numbers.
Wondering what all of this means? Check out the PTN Primer!
For the first seven weeks or so of the season, these metrics are based partially on a few projection factors, namely recent program performance, the effects of roster attrition, recruiting rankings, and sweet, sweet voodoo.
As the season progresses, data from games played will be factored in, with a progressively lighter emphasis on the projection factors. Starting about midseason, these metrics will be based purely on games played this season. At that time, we’ll also get splits for offense, defense, and special teams, as well as insights on how teams handle passing and short-yardage situations and how they manage field position.
2 | This last one’s not true.
You’re kidding, right?
Yes, you are seeing that correctly — the Tide lost, yet somehow got better in three of the four overall quality metrics, and hung on to the #1 rank in the fourth. What the heck is going on here?
3 | BAH GAWD THAT’S THE REC’S MUSIC!!!!
It’s still early in the season, and these numbers are still being influenced in some part by last year’s results. Starting Week 8 or thereabouts you’ll see some pretty interesting shifts when those adjustments are removed from the formulas, but for now they are still here and making an impact.
4 | FEI, for example, is currently at a 57/43 split between preseason projections and this season’s results, respectively.
5 | The week 8 part applies mainly to FEI — apparently we’re pulling preseason projections, etc. from S&P+ starting next week!
Turnovers, I think, may also be a culprit here. Turnover Margin, Turnover Luck, and Sack Rate are how those are accounted for in S&P+. The former two were obviously impacted last week, but the Tide’s sack rates through three weeks are pretty solid, at #27 overall on both sides of the ball. Furthermore, turnovers are just one factor in the S&P+ formula, so one bad game on that front won’t ruin your entire season in these numbers.
Only the most ardent Ole Miss supporters are of the mind that the turnovers weren’t a huge part of the Rebels’ success last Saturday, perhaps even the only factor that mattered in the game. When you strip away the impact of those turnovers — the short fields, the free possessions, and so on — Ole Miss was successful, but not to the same degree as what might be expected by the results of their first two games. That doesn’t matter on the scoreboard, of course, but it does matter in the metrics.
Is Alabama the best team in the country right now? No, I don’t think you can say that. These quirks sort themselves out over the course of the season, and starting here soon I think you’ll see the Tide — barring pandemonium around the country or a poor showing in Athens next week — settle into that 6-10 range that feels right at the moment. Last week’s loss took some shine off the Tide, but the Playoffs are still a realistic goal for this team — they’ll just need a bit of help to get there.
So, what do we know?
As noted, Alabama is more or less your consensus #1 in the advanced metrics right now — even FPI elevated the Tide to #4 after last week. Their opponent, Louisiana-Monroe, is slightly less well-regarded than the Tide, by about 100 ranks or so. Aside from the API tune-up in November, this is probably the worst team the Tide will play all year by a considerable margin.
It’s not all bad for the Warhawks, though. You’ll note we have additional S&P+ components to play with this week, so we know the Warhawks can do some good things when they have the ball. They are currently the #8 rated pass offense in the country according to S&P+, which is initially frightening until you note the Tide secondary, warts and all, is #10 overall against the pass. It can’t be overstated enough that all of the heartache over the defense this week is horribly misplaced. This is still an elite unit, and while the Warhawks may move the ball through the air at times, overall this is going to be a long afternoon for them.
The other side of the ball reveals what this game is going to be — many, many reps for the offensive line to polish their run blocking technique. Lousiana-Monroe is horrendous against the run, which is something the Tide has done quite well through three weeks. Expect to see Derrick Henry’s day done by the middle of the third quarter, and another quality look at the future in Damien Harris.
One aspect to keep an eye on when the Tide have the ball is when they don’t completely obliterate the Warhawks on first down and find themselves in a Passing Down situation. This is not the strong suit of the Tide offense, but it does appear to be what Louisiana-Monroe is best at defending. If the Tide consistently finds themselves in third-and-long situations, this game could get a bit interesting. That will surely happen once or twice, but not consistently enough to make a difference. The only real question here is whether or not the Tide will cover, honestly.
6 | Or the defense, for that matter, although they are still decent there.
Any intangibles to consider?
TRAP GAME! Nestled lovingly between physical, monumental SEC clashes with Ole Miss and Georgia, a throwaway contest against a totally overmatched Sun Belt team is the classic example of a game that’s easily overlooked. Something tells me practice this week has been, uh, loud, and I suspect in this case we’re going to see a righting of the ship moreso than a concerning struggle.
As you’re probably aware, the last time these two teams played was in Nick Saban’s first season with the Tide, and the Warhawks’ victory over the Tide in Tuscaloosa is perhaps not that shocking in hindsight — the 2007 team was not very good — but was certainly considered such at the time. All of the players and most of the coaches associated with that team are no longer around, but you better believe the team heard all about it this week.
It should be great football weather again this week, as it looks like the rain may hold off until Sunday and a nice, balmy upper 70s is in the cards for kickoff. I’m of course referring to Tuscaloosa, as this one is in the friendly confines of Bryant-Denny Stadium.
As far as I am aware Louisiana-Monroe is not dealing with any significant injuries. Aside from Robert Foster, who is unfortunately done for the year, the Tide are also healthy.
Swanson Giddiness Index
This is going to be a tough game, right Ron?
Yeah, I don’t think so either.
The Tide are winning this, there’s no doubt about that. The question, as I stated earlier, is whether or not they cover the spread. S&P+ says yes, FPI says no. This game is reminiscent of last year’s FAU and Southern Miss contests, both of which the Tide won by 40. That being said, the Tide haven’t yet hit 40 this season, and I’m thinking ULM gets a garbage time touchdown in there anyway. I just can’t see it happening this week — angry, vengeful Tide or otherwise.
STRAIGHT UP: Alabama Crimson Tide
AGAINST SPREAD: Louisiana-Monroe Warhawks