Our Defense, Their Offense - numbers offer hope!

Submitted by mistersuits on

[Ed.: Bump. As the OP notes, this data is still very shaky four games in, but the amount of improvement in the offense is so great it can hardly be a mirage.]

In my post the other day, Why should 2010 not be another 2009?, I looked at what our offense has accomplished in 2010 relative to what it had accomplished at this point in the season in 2009. It had two meaningful results:

1) This years' offense draws its potency from highly reproduceable, base set offensive plays, unlike the high variance scrambles and special teams play of 2009.

2) This year's offense is putting up far superior numbers to what they did a year ago (up 28%!!) against as-good or slightly-better competition (77th strength-of-schedule in 2010 vs 114th in 2009).

The Conclusion From the Former:

Our offense will come back to earth from meteoric numbers in out-of-conference play, BUT we have statistically significant evidence to believe that our offense will be far more reliable than last year due to depth, experience, and dilithium.

The Worry:

Our defense cannot stop any team that is executing, whether it's UMass or that-team-down-south. In other words, our wins and losses are going to be determined by how good an offense we face each week, and how well they execute.

Examples: UConn played bad (dropped passes, poor throws) and we stopped them. On the flip side UMass played well (good schemes, good execution) and they had their way with us.

Each and every Big10 offense we play is going to put up at least or slightly better numbers than their normalized offensive output.

So let's find out how bad it's going to be against us with a--

Chart of Infinite Defensive Gloom (after 4 weeks)

Rank Opponent N-PPG N-YPG SoS
1 osu 39.5 409.4 61.38
2 Wisconsin 31.2 381.7 59.93
3 Iowa 28.7 355.1 60.53
4 Connecticut 28.2 333.7 64.34
5 MSU 27.2 343.2 56.11
6 BGSU 26.6 310.7 72.20
7 Indiana 25.7 260.1 47.36
8 UMass 23.1 351.4 57.92
9 Notre Dame 23.0 426.3 75.99
10 Penn St 20.9 330.0 68.00
11 Illinois 20.7 294.0 62.24
12 Purdue 17.3 297.9 60.47
 
2009 Chart (requested by commentors)
 
2009 Rank 2009 Opponent Expected N-PPG Expected N-YPG Actual PPG Actual YPG
1 MSU 32.5 404.7 26 417
2 Wisconsin 30.7 402.8 45 469
3 Notre Dame 30.0 455.0 34 490
4 osu 28.8 366.0 21 318
5 Penn St 27.4 387.7 35 396
6 Purdue 27.2 383.1 38 494
7 Illinois 24.1 391.7 38 500
8 Iowa 23.2 336.3 30 367
9 Indiana 22.7 352.8 33 467

 


Metrics

Normalized Offensive Output - The important thing we're doing here is not looking at the raw PPG and YPG of these teams because it does not account for how good of competition they have played. Four weeks in, the SoS data is far from reliable, but it is at least forming.

Our opponent with the strongest SoS serves as the baseline (Notre Dame with 3 Big10 teams and Stanford). In other words, these numbers estimate what all of these teams' offenses would have generated if they had all played Notre Dame's schedule thus far (Purdue, Michigan, MSU, and Stanford).

Strength of Schedule is taken from Sagarin rankings. (BGSU and UMass are going to have way-inflated numbers at this time, but I included them on the chart anyway as a reminder this is not a perfect analysis and as an interesting couple of data points to track as the season progresses.)

N-PPG or Normalized Points-per-game is taken from the teams average PPG with a SoS multiplier factored in to deflate numbers from playing bad competition and inflate numbers based on playing good competition.

N-YPG or Normalized Yards-per-game is calculated using the same SoS multiplier as N-PPG but using this metric will help us determine a less variant guess as to how offenses will perform (PPG is subject to wild variance based on turnovers and special teams).

I am only tracking our 12 opponents because the only thing that matters is the twelve games Michigan plays and I don't want to get depressed that we are playing Wisconsin and Iowa instead of NW and Minnesota.

Results

This chart pans out as expected. That-team-down-south is the clearcut leader. (Michigan is actually second in N-PPG with 36.3 but FIRST in N-YPG with a staggering 494.5).

We see a clearly defined pecking order in the Big10 that matches very closely the general consensus: clear-cut leaders in OSU-Wisconsin, a muddled middle of Iowa-MSU-Indiana, and a struggling bottom of offenses PSU-Illinois-Purdue.

The exceptions are Indiana, which is trending higher up the rankings due to its offense, and Penn St, which was generally considered a top-4 team in the Big10 going into the season (but is clearly not the case with their offense).

UMass and BGSU will continue to fall down this chart as their SoS gets watered down with conference and 1-AA play.

Conclusions Based on Not Enough Data

NSFMF! Teams always seem to play their lights out when they play Michigan. Michigan's defense has a way of making teams look better than they are. Notre Dame for instance had their highest offensive output of the year against Michigan, operating at 125% of their average YPG.

If we take the MOST pessimistic view and give our opponents 125% of their offensive AND scoring outputs against us and only give ourselves 80% (assumption our offense slows down entering league play) of our average going into the Big10, Michigan ends the season 7-5 with wins over PSU, Illinois, and Purdue.

But remember:

Rank Team N-PPG N-YPG SoS
-- Michigan 36.3 494.5 66.77

If instead we give ourselves just our average offensive production going into this weekend - our Big10 expected record jumps to 6-2... 10-2 overall!! - with losses coming from Wisconsin and that-team-down-south.

Where does the truth lie? Probably somewhere in between 6-2 and 3-5. Would you take that outcome at the start of the season? In a heartbeat? I know I would.

It is going to be tremendous to watch this Michigan team storm into the Big10 season knowing that our offense only needs to hold serve and our defense can surrender season-best performances from every single opponent and we still have a fighting chance in all of those games!  And lest we forget... DILITIHIUM!

For now, I think we can look at this and add one more reason to the growing pile of why 2010 is NOT 2009! Get excited! Indiana here we come!

Prediction for Indiana:

Efficiency Team N-PPG N-YPG
125% Indiana 32.2 325

Michigan's ground game operates at MINIMUM of 100% our normalized average and puts up above-average PPG, but since we only score touchdowns we go to the next closest number after 36! Indiana plays their lights out and operates at 125% of their normalized efficiency, mostly through the air.

Michigan 42
Indiana 31

GO BLUE!

Comments

TXmaizeNblue

September 30th, 2010 at 8:37 PM ^

I love statistics and crunching numbers like this, but there are far too many variables that enter into one football game that make such projections very unreliable.  For example, just look at the UConn numbers.  According to the chart Michigan's D did about 3 times better than expected, and UMass scored 14 more pts then their N-PPG.  

Anywho - thanks for the work!  I don't know how you guys have time for such things!  Glad we have avid UofM fans :O)

I do think Michigan will end up with a +1/-1 BT record.

mistersuits

September 30th, 2010 at 9:12 PM ^

It's less about what we did to stop UConn than UConn stopping themselves, I think.

We have to root for opponents' offenses to falter of their own will for the most part - dropped passes, throwing balls out of the endzone, turnovers, and poor play calling. These charts assume that our opponent will execute at least up to their average level of play and anything less is a bonus for us!

c-man

September 30th, 2010 at 10:06 PM ^

Very interesting...

So with the addition of the 2009 data, I wondered if there was a way to refine the games-won estimate. My read is that mistersuits subtracted Michigan's N-PPG of 36.3 from opponent's N-PPG (or 125% of N-PPG). Just for fun, I wondered what including some randomness might yield...

Some notes and assumptions:

  • Opponent output vs Michigan in 2009 averaged 124% of the rest of their schedule with a standard deviation of 0.3. I used that as the baseline for 2010.
  • I assumed opponent points scored is normally distributed with a mean of 1.24 * N-PPG and stdev of 0.3 * N-PPG
  • I assumed Michigan's scoring is also normally distributed with a mean of 36.3 and stdev of 0.3 * 36.3 = 10.8 (just used the 2009 opponent data for simplicity)
  • The difference between Michigan and opponent's score is normal with mean 36.3 - 1.24*N-PPG and stdev of sqrt(10.8^2 + 0.3*1.24*N-PPG^2)

This yields probabilities of Michigan victory of:

Team p(Muppets) Expected wins
Connecticut 54%  
Notre Dame 72%  
UMass 71%  
BGSU 59%  
    2.6
Indiana 62%  
MSU 57%  
Iowa 52%  
Penn St 79%  
Illinois 79%  
Purdue 88%  
Wisconsin 44%  
tOSU 24%  
    4.9
    7.4

For the 4 games in the bag, this seems pessimistic (based on this, there's only a 16% chance of willing all four games). What happens if we dial all of our opponents back to 100% of expected PPG output?

Team p(Muppets) Expected wins
Connecticut 72%  
Notre Dame 85%  
UMass 85%  
BGSU 77%  
    3.2
Indiana 79%  
MSU 75%  
Iowa 71%  
Penn St 89%  
Illinois 90%  
Purdue 94%  
Wisconsin 64%  
tOSU 42%  
    6.0
    9.2

9.2 expected wins on the season, 6 in conference play. The probability of winning the first four games is now up to 40%.

An attack of the Angry-BLANK-Hating-God on the offense (or just tougher Big Ten defenses) that cuts Michigan PPG production by 25% would yield 3.1-4.4 conference wins.

The first couple Big Ten games will obviously tell us a lot, but this year has been a lot more fun than the last three...

The Rake

September 30th, 2010 at 11:55 PM ^

This is a wild but very cool site. I love the stats, would just love for us to live up to them on the field in Big Ten play.  I wouldn't mind a 42-31 win, or even a 35-24 win.  I just want to see this team (and Rich Rod) succeed.  I think RR can be great for us and I think you are seeing the makings (clearly) of one of the sickest offenses in Michigan history.  I think we need to win the next 2 games to make our season and try to get to 8-4, that is my goal.  Pumped for this game (although I wish we were healthier with Shaw out and obviously thin secondary).  Peace.

The Rake

http://thefilmnest.com

Blue Blood Strip

October 1st, 2010 at 8:31 AM ^

means so much this year.  I really dont think enough people realize the possible ramifications the results of this year can have both positive and negative.  Its a tight rope walk this year.

But so far so good.  Go blue!