The Michigan Difference - Purdue Edition

Submitted by TennBlue on November 15th, 2010 at 7:06 PM

OK, this isn't a hard-core statistical analysis like the Mathlete would do, just some fun with numbers.  We have a rather bipolar team this year (Offense #5 in TO, Defense #105 in TD), and I thought it would be interesting to look at what our opponents' Total Offense and Total Defense stats would look like if they hadn't played us - and what kind of a difference it would make in their overall ranking of NCAA stats. 

The NCAA stats are not linear, of course, and a difference of 1 yd/gm can be a large or small difference in rankings depending on how closly spaced everyone is.  So as I cautioned, this isn't a hard-core statistical exercise.  It is interesting to look back at the early games and see how well we did in comparison to what other teams ended up doing against them - what seemed like a good or bad performance at the time may look different in retrospect.


Part the First: Offense

We know our offense is great, but what kind of damage has it done to the Total Defense (TD) ratings of our opponents?  Here they are thus far:

Opponents' Total Defense, Season
Opponent Games Yards Yielded Yds/gm NCAA Rank
Connecticut 9 3277 364.11 56
Notre Dame 10 3803 380.30 66
Bowling Green 10 4205 420.50 94
Indiana 10 4116 411.16 89
Michigan State 10 3279 327.90 28
Iowa 10 3070 307.00 16
Penn State 10 3567 356.70 52
Illinois 10 3448 344.80 38
Purdue 10 3644 364.40 57


What would these guys' defensive stats look like if they hadn't played Michigan?

Michigan Offensive Performances
Opponent Total Offense, M

Opp. Avg - M,

M Total Offense,
% of Opp Avg - M**

Without M

Connecticut 473 350.50 135% 46
Notre Dame 532 363.44 146% 56
Bowling Green 721 387.11 186% 77
Indiana 574 393.56 146% 78
Michigan State 377 322.44 117% 27
Iowa 522 283.11 184% 6
Penn State 423 349.33 121% 44
Illinois 676 308.00 219% 18
Purdue 395 361.00 109% 53

*Opponents' average Total Defense yards per game, minus the Michigan game

**Michigan's Total Offense in game as a % of the opponent's average TD minus the Michigan game

So Michigan has gained above our opponents' average yardage yielded in every game thus far, and their TD ranking has suffered as a result.  What's the damage?

The Michigan Difference, Offense
Opponent TD Rank With M TD Rank Without M Difference
Connecticut 56 46 -10
Notre Dame 66 56 -10
Bowling Green 94 77 -17
Indiana 89 78 -11
Michigan State 28 27 -1
Iowa 16 6 -10
Penn State 52 44 -8
Illinois 38 18 -20
Purdue 57 53 -4

Average change in Total Defense ranking for all opponents:  -10.1 places.


Part the Second, Defense

So the flipside of this, then, is how much has our defensive suckitude helped out our opponents stat sheet?  Where would they rank in TO without having played us?  We'll run the same tables again, but from the opposite tack:

Michigan Opponents' Offensive Performances, Season
Opponent Games Yards Gained Yds/gm NCAA Rank
Connecticut 9 3057 339.67 87
Notre Dame 10 3874 387.40 49
Bowling Green 10 2883 288.30 114
Indiana 10 3915 391.50 53
Michigan State 10 4168 416.80 34
Iowa 10 4049 404.90 46
Penn State 10 3597 359.70 74
Illinois 10 3671 367.10 71
Purdue 10 3051 305.10 107

First thing that jumps out at me is that none of these are world-beater offenses thus far.  They're functional and solid for the most part, but even the best is merely above average.  We can't really blame our bad defensive performances on having come up against a bunch of awesome offenses.  Anyway, how'd they do against us?


Michigan Defensive Performances


Total Offense, Opp

Opp. Avg - M,


Opp Total Offense,

% of Opp Avg - M**


Without M

Connecticut 343 339.25 101% 88
Notre Dame 535 371.00 144% 68
Bowling Green 283 288.89 98% 114
Indiana 568 371.89 153% 67
Michigan State 536 403.56 133% 50
Iowa 383 407.33 94% 44
Penn State 435 351.33 124% 78
Illinois 561 345.56 162% 85
Purdue 256 310.56 82% 105

* Opponents average offensive performance, minus the Michigan game

** Opponents TO as a percentage of their average offensive performance, minus the Michigan game

To summarize:

The Michigan Difference, Defense
Opponent TO Rank With M TO Rank Without M Difference
Connecticut 87 88 +1
Notre Dame 49 68 +19
Bowling Green 114 114 0
Indiana 53 67 +14
Michigan State 34 50 +16
Iowa 46 44 -2
Penn State 74 78 +4
Illinois 71 85 +14
Purdue 107 105 -2

Average boost to opponents' Total Offense NCAA ranking: +7.1 places

So we've had four really bad defensive outings (ND, Ind., MSU, Ill.) and a four decent ones (UConn, Iowa, PU, BG).  The PSU game doesn't look so bad from this perspective - still not good, but far from our worst outing when compared to others.

Part the Third:  Summary

The Michigan Difference, Overall

Michigan's O Difference

on Opp TD Ranking

Michigan's D Difference

on Opp TO Ranking

Connecticut -10 +1 W, Good O, OK D
Notre Dame -10 +19 W, Good O, Terrible D
Bowling Green -17 0 W, Awesome O, OK D
Indiana -11 +14 W, Good O, Terrible D
Michigan State -1 +16 L, OK O, Terrible D
Iowa -10 -2 L, Good O, OK D
Penn State -8 +4 L, Good O, Bad D
Illinois -20 +14 W, Awesome O, Terrible D
Purdue -4 -2 W, OK O, OK D

Takeaways from these numbers (as opposed to other numbers or observations):

  • We played well at Iowa and were beaten by a better team.
  • We played badly against MSU on both sides of the ball; they might have beaten us anyway with good performances, but not likely.
  • The loss to PSU doesn't look like such a bad outing from this angle.  Maybe PSU is better than we gave them credit for.
  • Awesome offense wins, terrible defense doesn't necessarily lose.
  • Our offense is better at offending than our defense is bad at defending.
  • Winning is more fun than losing.



November 15th, 2010 at 7:41 PM ^

Nice analysis but it's hard to draw conclusions...the + and - numbers don't necessarily correlate to a win and a loss.

I think that the youth of this team also makes it hard to quantify what your going to get out of them.  Each game is a different story.

Let's just hope the next two are focused with execution at a high level.

Tully Mars

November 15th, 2010 at 9:56 PM ^

I had been wondering about these numbers recently.  Thanks for taking the time to get them out there to us.

I think it's interesting that except for Iowa, our 'good' D performances come against bottom-half offenses.  That doesn't seem to bode well for Wisconsin (#27 TO) and Ohio State (#17 TO).  


November 16th, 2010 at 12:52 AM ^

you'd think over the course of the season that some sort of improvement will be season on the defensive side of things.  hopefully, at least one of these last two weeks results in a performance where we can infer that our D has at least gotten better due to their trial by fire experience.



November 16th, 2010 at 7:13 AM ^

Very interesting analysis - thank you for the effort.

A couple of stats that might have reduced net gains by opponents would be short fields from less than stellar kickoffs and short fields from the numerous TO's which have happened since the start of of Big Ten schedule.  Obviously, an INT in the end zone, such as with MSU would have little impact on an opponents starting field position, but with Iowa, just the opposite was the case.

Hopefully the TO gremlin will be gone the next couple of games - weather for Saturday looks pretty good at the moment  - that might help.


November 16th, 2010 at 2:00 PM ^

But it was complicated enough digging out all these numbers and there were too many charts as it was.  I'm just having fun with the "what if they hadn't played Michigan" concept.  All conclusions are dubious at best.

3OT only added 75 yards of TO to both teams' totals.  Not a huge difference - and the NCAA rankings include the OT totals, anyway.