Today's Fun Fact

by Jeff Sullivan on Aug 10, 2010 12:06 PM PDT in Seattle Mariners Stats

I forgot all about this spreadsheet I put together in May. Since 1990 - which is as far back as I felt like going - there have been 53 instances of a team replacing its manager with another in-season, with each manager lasting at least 20 games. The numbers:

Manager #1:

1600-2153
Total win percentage of 42.6%
Average win percentage of 41.6%

Manager #2:

2140-2394
Total win percentage of 47.2%
Average win percentage of 46.8%

Naturally, we can assume that a big part of this is simple regression to the mean. Teams generally end up firing their managers when they're underperforming relative to expectations, and teams that are underperforming relative to their expectations tend to regress north over time. We must also be aware that (1) 53 instances isn't an enormous sample size, and (2) teams change over the course of a season, and manager #2 will not be leading the exact same team as manager #1.

Still, it's interesting. Manager #1's average winning percentage corresponds to a full-season record of 67-95. Manager #2's average winning percentage corresponds to a full-season record of 76-86.

0 recs | 37 comments

Comments

Given that underperforming teams tend to deal players for prospects

wouldn’t the changes that take place tend to make Manager #2’s teams less competitive rather than more?

The Ancient Mariner - August 10, 2010 reply

The opposite could be argued

That teams, underperforming to the extent that they fire their managers during the season, change course by not only firing Manager #1, but by making changes to the on-field makeup that is losing baseball games. Whether that means more young players on the field or not, either way they reached a point that made them willing to try new players, batting orders, alignments, etcetera.

A psychological effect could be argued as well: that with an interim manager the players feel less pressure in what becomes a kind of extended tryout in a lost season.

lemonverbena - August 10, 2010 reply

Underperforming teams also tend to cut players who sucked a lot in the first half

chaney - August 10, 2010 reply

So you're saying we should hire this mystery Manager #2?

Eyebrows - August 10, 2010 via mobile reply

Could there also be Hawthorne (observation) and team reacting to a change (novelty) effects?

Adding to the regression effects.

infield power - August 10, 2010 reply

Why phrase this as a question?

Of course there could be. There’s not really a way to disprove it.

Matthew - August 10, 2010 reply

The top ten defensive reactions to being challenged out by a local authority

10 Don’t yell at me, I’m scared

9 Hey look, Ken Griffey just hit a home run!

8 Why phrase your response as a question?

7 Because I am arrogant and opinionated, but am trying to fake people into thinking that I’m not.

6 To avoid Male Answer Syndrome.

5 According to the LL commenting guidelines: “An easy way to make sure others feel welcome is to tack a question on to the end of whatever you want to say. By making it a question instead of a statement, you invite other people’s opinions to come along.”

4-2 Why not?

1 Bite me!

infield power - August 10, 2010 reply

Matthew's response could have been phrased better

but this is full on dickish.

pdb - August 10, 2010 reply

Thanks, I really tried. Do you have any suggestions for 3, 4 that would have made it go further over the top?

infield power - August 10, 2010 reply

You know what? I wasn't even trying to be a dick to you.

I was seriously asking why you stated it as a question.

But hey, thanks for letting me know how you handle feeling slighted.

Matthew - August 10, 2010 reply

Dude has yet to get a ball into the outfield. He's feeling pretty low.

Sec 108 - August 11, 2010 reply

I'd bet that if we looked at teams that didn't fire their manager

We’d find nearly the exact same improvement over the rest of the season. But that sounds like a lot of work.

davidcameron - August 10, 2010 reply

Based on no information, I agree with you

I imagine a ton of this is just regression, if not all of it. But because I don’t know for sure, and because this spreadsheet took a few hours, post!

Jeff Sullivan - August 10, 2010 reply

So if you picked the average/mean date of all mid-season managerial changes

Then looked at the records past that date of every team that didn’t fire their manager, you think they would also average an improvement of ~5%? That would mean that ALL teams regress upwards in the latter part of the season. Correct me if I’m wrong, but that doesn’t seem possible. One team wins and one team loses every game played.

lemonverbena - August 10, 2010 reply

It's not that all teams regress upwards

It’s that managers who get fired tend to be fielding teams that are some combination of bad but also having bad luck. The bad luck was part of the reason they got fired a lot of the time, and the new manager benefits from the regression upwards with better results.

OlSalty - August 10, 2010 reply