UM/MSU/ND: A Study in Mutual Opponentism

INTRODUCTION

This diary is an attempt to answer the following question:

Can the results of the Michigan/Notre Dame and Michigan State/Notre Dame football games be used to predict the results of the Michigan/Michigan State game?

INSPIRATION

State plays Notre Dame before we do this year.  I thought that was unusual, but I wanted to see just how unusual it was.  From there, I thought it would be interesting to compare the results of the games between the three teams on any given year, and see how closely related UM's and MSU's performances against Notre Dame can be matched to their performances against each other.

RAW DATA

I decided to look back at the last 20 years in which Michigan, Michigan State, and Notre Dame all played each other.  In 2000 and 2001 MSU played ND but Michigan did not.  In 1995 and 1996 neither MSU nor UM played ND.  Therefore the data spans from 1988 from 2011 with a few gaps in between.

terms:

First notes which team (MSU or UM) played Notre Dame first that year.

HOME TEAMS are in bold.  Each series alternates sites yearly, and the three series are synced up such that each team has one home and one away game.  Rather well done on the part of whoever made that work.

MOV Diff is the difference in margin of victory of the two Michigan schools over Notre Dame, with MSU's MOV subtracted from Michigan's MOV.  A higher number means Michigan did better against Notre Dame than State did.  A negative number indicates State did better against ND.  Example:

1997: UM defeats ND 21-14: MOV 7.  MSU defeats ND 23-7: MOV 16.  MOV Diff = 7-16 = -9.

MOV is Michigan's margin of victory over Michigan State in the UM-MSU game.  A negative number indicates Michigan lost

DNP means the teams in question did not play each other that year.

* This game gets an asterisk because it was BULLSHIT.  That is all.

I PROCESS INFORMATION BETTER GRAPHICALLY THAN I DO TEXTUALLY DO YOU THINK MAYBE WE COULD HAVE A SCATTER PLOT?

HEY THAT'S TRENDING UPWARD

Just barely.  It's more like a shotgun blast than a linear trend.

• When Michigan outperforms State in MOV Diff, Michigan beats State 69.2% of the time.  When Michigan does NOT outperform state in MOV Diff, Michigan beats State 57.1% of the time.  That's a slight correlation.
• When Notre Dame splits its series against Michigan and State, the team that beat Notre Dame is the team that wins the UM/MSU game exactly 50% of the time.  That's zero correlation. 
• When Michigan comes out on top of the split it goes on to beat State 60% of the time.  When State comes out on top it beats Michigan 33.3% of the time.  Overall Michigan has beaten State 62.% of the time.
• When Notre Dame beats both Michigan schools, Michigan beats State 77.8% of the time, and when Notre Dame loses to both, Michigan beats State 60% of the time. 
• MOV Diff and MOV are within two touchdowns of each other 9 times out of 20.  The other 11 times they are further apart.  The most extreme disagreement was in 1998 when Notre Dame beat Michigan by 16, then fell to MSU by 22... but then Michigan beat State 29-17.

BULLET POINTS THAT ARE SORT OF FUN BUT NOT DIRECTLY RELATED TO THE ORIGIONAL QUESTION

• Michigan's Head-to-Head record against Notre Dame since 1988: 10-9-1
• Michigan State's Head-to-Head record against Notre Dame since 1988: 10-12.  State's actually 10-5 against ND since their 1995-1996 break; before that MSU hasn't beaten Notre Dame since 1986.
• Michigan's Head-to-Head record against Michigan State since 1988: 15-9**
• State playing ND before Michigan does is indeed highly unusual: it's only happened once in the last 24 years - in 1997.  That's right:  Every time MSU plays Notre Dame before Michigan does, Michigan wins a National Championship.
• Since Overtime began in 1996, the UM/MSU game has gone to overtime three times, the MSU/ND game has gone to overtime twice, and the UM/ND game never has.

**but one of those losses was BULLSHIT.

YOUR STATISTICS ARE BAD AND YOU SHOULD FEEL BAD

Pretty much, but I spent all this time making the graph and there hasn't been a new diary in two days so I'm posting it anyhow. 

SUPPOSING FOR A MOMENT THAT I TOOK THESE STATS SERIOUSLY WHAT CAN I EXPECT?

Well, first of all since we're playing Notre Dame after State does: National Championship.  I mean, it's right there in the data.  Apart from that, if State beats Notre Dame and then Notre Dame beats us don't panic - of the 3 times that's happened in the past 20 years we've gone on to beat State twice anyhow.  Likewise don't get too confident if Notre Dame beats State but loses to us.  Don't put a lot of stock into the Michigan schools' respective margins of victories in the two games against Notre Dame - more often than not, it turns out to be meaningless when Michigan and State take the field against each other.