Michigan has played the #1, #3, #5, & #6 SP+ defenses this year- & it just doesn't matter!

Submitted by RealElonMusk on December 2nd, 2022 at 3:05 PM

And has scored vs #1 -  27 points, #3 17 points, #5  45 points, #6   41 points   

There is not a statistical correlation in B10 play between opponents defensive ranking & the number of points Michigan scores!   


swn

December 2nd, 2022 at 3:35 PM ^

Just goes to show that you always have to take statistical models with a grain of salt. They can only be as good as the data feeding them. And sometimes they have inherent biases/flaws like the kenpom Wisco problem from some years ago where they were always wildly over ranked because of style of play.

jmblue

December 2nd, 2022 at 3:18 PM ^

Honestly, this is probably evidence of the limitations of SP+.  I tend to doubt that we actually faced four of the six best defenses in the country this season.

M-GO-Beek

December 2nd, 2022 at 4:16 PM ^

I agree with this take.  When you are describing teams in the middle of the bell curve, it probably does very, very well, but when you are talking about facing either end of the spectrum on either side of the ball, I suspect the model does not hold up as well.  It is one thing for an average receiver to catch a pass in space and be tackled right away, but there is no way for the model to know that if it is an elite receiver, that player scores a TD.  By necessity, it treats all players on a team as a single unit, when individual match ups are often what makes the difference between a big play or a stop and that is a lot harder to model.

King Tot

December 2nd, 2022 at 4:32 PM ^

These "top 10's defenses" are Illinois, Iowa, OSU and PSU. They rank 3rd, 5th, 12th, and 18th in total defense (not a great metric) and 3rd, 2nd, 8th, and 5th according to FEI. (Michigan was 2nd, 4th)

Some of this is a result of a weak B1G but Iowa had to play U of M and OSU in crossovers and didn't get to pad their stats by playing their own offense.

 

Newton Gimmick

December 2nd, 2022 at 5:16 PM ^

SP+ is opponent adjusted though.  It's why Clemson was outside the top 10 even when undefeated (historically weak ACC).  People say the Big 10 is down and the West is bad (both relatively true) but it's still solidly the 3rd best conference -- and 2nd best by some other power ratings -- and the West is still about equal to the ACC Atlantic (which is far better than the Coastal).

Bill Connelly said the only way these defenses might be overrated is that they are designed to play other Big 10 teams in coldish weather, and thus might not perform as well when out of region vs teams of a different style.  But that shouldn't downgrade what Michigan has done.

GoWings2008

December 2nd, 2022 at 3:19 PM ^

I'd argue that defensively is the most important statistic, especially looking at The Game. One could argue that momentary breakdowns in their defense allowed the big plays, but holding that "high powered" offense to 3 pts in the second half is what made that victory possible. 

 

YES, osu fans...you got dominated.

xgojim

December 2nd, 2022 at 5:59 PM ^

Agreed.  On the other hand, controlling the play with its run-oriented offense has typically kept the opponent off the field so they couldn't score.  And when the opponents had the ball, the defense was dominant and caused the ball to be turned back to the offense pretty quickly.  Except against OSU, when the lightning scores meant that it didn't really matter to use up the clock.  M won going away.

M-Dog

December 2nd, 2022 at 3:52 PM ^

#1, #3, #5, & #6 SP+ defenses in the country, or just in the Big Ten?

I highly doubt that we have played the #1, #3, #5, & #6 SP+ defenses in the country in a "for real" sense.

mistersuits

December 2nd, 2022 at 4:10 PM ^

Iowa and Illinois have great, if not elite defenses, and the other two are PSU and OSU. Maybe they're not all top-5 but I would be hard pressed to say they aren't top-15. And in terms of hypothetical future opponents those are all better defenses than anyone else left except Georgia.

King Tot

December 2nd, 2022 at 4:53 PM ^

If there are frauds of those 4 it is PSU and OSU. Both dropped 5 spots after playing us. Both have some great athletes and/players but weaknesses and questionable coaching.

MGoCarolinaBlue

December 2nd, 2022 at 5:05 PM ^

Ranking should not be used this way, because it is just an ordering and doesn't convey the actual strength of the defense. It's very non-linear, for example in your table we can see that the #1, #3, and #5 defenses have ratings of 10.2, 10.7, and 11 points allowed, while the next ranked defense at #6 has a rating of 15.4 points allowed. Then all of the mid-ranking defenses are clustered quite closely together in terms of their ratings as well.

It would be far more informative to test the correlation of Michigan's offensive production vs. the rating of the opposing defense.

Also, since S&P is a tempo adjusted statistic, this should be done in terms of points per offensive drive, and probably adjusted for starting field position.

alum96

December 2nd, 2022 at 5:32 PM ^

Have you seen big 10 offenses ? Name me the 6th best one.  Defense stats are going to be padded in this conference just as offense is in the big 12.  

jbrandimore

December 2nd, 2022 at 10:22 PM ^

When you see a stat like this that is highly impossible- meaning there’s no way the Big Ten includes half the top ten - you need to consider trashing the stat in favor of something better.