[Ed-M: Bumped to Diaries]
(Click for larger)
I looked at the coaching records of new hires since 2001. There's a pretty wide spread. I looked at returing starters vs. this data but the data I have is incomplete. Hopefully this comes out. My wife is about to pull the plug on me.
I don't have time to play with the sizing here. This has some value maybe. If I come back to this I'll add more detail.
The negative 10 outlier is Stan Parrish following Brady Hoke at Ball State...
[Ed-M again: Adding some thoughts so I can get this to 200 words and bump to Diaries.
The bell curve here suggests the data are pretty solid, but a Delta of +0.5 or 1 wins for a new coach seems really really good. Reason being, look at the third chart, with the coaches who took over 12-win teams. We're not talking about replacing just fired guys, but also those who moved up or moved on after dream seasons. Michigan is in that 7-win area where only two teams improved.
So is there an advantage gained from having a 1st-year coach? This doesn't say, but it's not a massive disadvantage, which is what I kind of expected would happen.
I think this needs to show the difference between coaches replacing a fired guy (which suggests there was a level of suspected incompetence) versus a coach brought in to replace a legend or retiree, who in turn was followed out the door by most of his starters. In other words, it's gotta pull out the noise. There's plenty of that around, since we can expect the circumstances of the team that lost 10 more games from the year before had a lot more going into them than Stan Parrish (meh) taking over for Brady Hoke (RAWR!)].