04 March 2016

CF To RF Defensive Modeling: Austin Jackson Is Dexter Fowler


On Monday, I wrote about how the loss of Dexter Fowler did not make or break the season.  In that article, I wrote about defense in a very conventional wisdom-y sort of way:
The above obviously does not take into account fielding prowess of any of the players.  [Nolan Reimold and the rest of the current COFs on the roster are] defensively worth about -10 runs, which would be the same as the David Murphy, Pedro Alvarez, David Freese, and Matt Kemp options.  At -5, Dexter Fowler, Jay Bruce, and Nick Markakis.  Austin Jackson and Oswaldo Arcia fall in either at league average or +5.  Marcel Ozuna is either at +5 or +10.  Anyway, that is the rough way to look at it through this one data science way of looking at it.
And that is a rough way to look at it.  In fact, the whole center to corner conversion has been gnawing at me for a few months because we simply wave a magic wand and simply say +10 runs.  To test this all out, I looked for centerfielders who shifted over to right field in their late 20s and early to mid 30s.  I had two approaches, a simple conversion and then regression modeling.  I created a regression model which compared their last two seasons at centerfield to their first two seasons in right field.  I included age modeling, but by this point in a career, fielding is largely settled with only minor shift.  Your major decreases in fielding tend to occur in a player's early to mid twenties.  Anyway, I tested age as a variable and found it meaningful only for error rates, which is the only metric (i.e., UZR's ARM, RangeR, Err) that appears to greatly change within this age group.

The players considered in this sample were likely quite few (10): Carlos Beltran, Ichiro Suzuki, Torii Hunter, Curtis Granderson, Randy Winn, Shane Victorino, Marlon Byrd, Alex Rios, David Dejesus, and Cody Ross.  With so few, there certainly might be some selection bias.  As in, the players in this grouping might be unique in comparison to the players we might choose to compare this group to.  Austin Jackson and Dexter Fowler might be different from this grouping in some way that would meaningfully make any comparison have minimal value.  That said, I cannot imagine at the moment why.

Anyway, there are certainly differences between defensive values from the centerfield values vs. the right field values (0.01) for this group.  A simple averaged conversion would be to adjust the ARM, RangeR, and Err values by 1.5, 7.6, and 0.1, respectively, over 150 games.  That, of course, sums up as 9.2 runs improvement.  That gives some credibility to the nonchalant +10 mark.

Here are those results:

Average
ARM(rf)
RangeR(rf)
Err(rf)
UZR/150
Austin Jackson
-2
5.6
0.4
4.0
Dexter Fowler
-2.7
-7
0.0
-9.7
Adam Jones
10.5
1.6
1.1
13.2
Marcel Ozuna
6.5
-5.4
2.6
3.7

However, the regression model (0.17) sees things a little different.

Regression 
ARM(rf)
RangeR(rf)
Err(rf)
UZR/150
∆CF
Austin Jackson
1.9
9.9
1.1
12.9
13.5
Dexter Fowler
2.1
0.8
-0.4
2.5
16.8
Adam Jones
10.5
7.0
0.9
18.4
9.8
Marcel Ozuna
3.5
2.0
2.3
7.8
8.6

I added Adam Jones in there just to see how he is projected with a move to right field.  Marcel Ozuna I considered because the Miami Marlins are looking to replace Carter Capps.  It probably is a pipe dream, but the Marlins could deal Ozuna and then sign Jackson.  Anyway, I simply wanted to put that projection on the table.  The real comparison I was interested in was the one between Jackson and Fowler.

As you may remember, the lineup modeling tool projected Fowler's presence in the lineup to be 13 runs greater than Austin Jackson's contributions there.  However, the defensive modeling performed in this post put Jackson's glove trumping Fowler by 10.4 runs.  In the end, that suggests Fowler is worth only 2.6 runs more than Jackson.  That is about 0.3 wins.  The regression model is indicating that a blanket 9.2 run increase in defensive value might well be inappropriate.

If we consider the regression modeling problematic due to having low significance (0.17), then we might feel more confidant going back to the original averaged conversion.  In that case, our expectation is that Jackson is 13.7 runs more valuable than Fowler, defensively.  All together, it makes Jackson 0.7 runs more valuable.

So, yes, as I wrote on Monday, keep calm.  Fowler probably was not that big of a catch.

23 comments:

Roger said...

So where are our rumors a bout the O's trying to sign Jackson? No QO, so what's the downside?

Jon Shepherd said...

Being reported in the press repeatedly as having interest since the Fowler deal went through?

Roger said...

not that I've seen reported.... Link, please? Not with any serious interest that I'm aware of.

Jon Shepherd said...

It has been in the local papers and press as contacts. You can google that if you wish.

Matt Kremnitzer said...

Here's one: http://www.masnsports.com/school-of-roch/2016/02/orioles-sifting-through-right-field-possibilites.html

Anonymous said...

Did the Orioles just sign Cuban OF Felix Perez?

Weav said...

Jay Bruce..They need a power bat. Get him?

Jon Shepherd said...

I have been told that.

Jon Shepherd said...

Isn't power the one thing they have?

Pip said...

Why?
Bruce hits lousy(career .248) he is a negative defender by every metric, except last year he was Positive in DRS.
His OBP was .294.
TWO NINETY FOUR.
The Reds want to get rid of him so badly they would probably give him away just to get rid of his contract. Why do you want him, why does any reasonable human being think we should pick him up?

Anonymous said...

Worley > Gonzales for alot less money!

Anonymous said...

Bruce is gold glove caliber compared to Reimold!

Anonymous said...

O's have a great history in picking up Reds right fielders!!!

Jon Shepherd said...

You must really like Chris Dickerson.

Jon Shepherd said...

Probably about 5 runs difference between them. Maybe Bruce is finally healed from the knee injury that has bothered him for a couple seasons.

vilnius b. said...

Thanks for the analysis. When you factor in Ajax' defensive superiority (something Showalter loves) over Fowler, you don't lose much.
Jackson's OBP leaves something to be desired, but he can steal a few a bases for us and most important: no draft pick lost.

Some other things of note: while he has a high K% for a batter who doesn't possess much power, he has consistently had a low percentage of pop ups (IFFB)---the easiest out of all batted balls that are in play. So that's encouraging. And judging from the percentage of bunts he converted to hits last year, he's hasn't lost that much speed going down the line. Cut the grass a little higher when he starts.

All in all, sounds like a good investment to make. What other teams are interested in him though?

MOB said...

Were any of these findings in your regression statistically significant? I find it hard to believe that you could find much in terms of meaningful findings with only 40 (10 players x 4 seasons) observations, limiting your degrees of freedom to 30 with 6 variables of interest plus 4 fixed effects for the players. Nonetheless, it's a creative approach to answering this question and I'm probably missing something here. For instance, maybe your unit of observation was player games over four seasons, thereby increasing the N considerably. Just curious.

Jon Shepherd said...

I answered significace in the article and discussed issues with selection bias. Only thing I did not mention is that my cutoff for innings was 1500. Most were over 2000.

Unknown said...

Moot point now. White Sox just signed him.

Frankly, he would be an offensive disaster, imo. And I
certainly do not want a Punch and Judy hitter in my RF.
I want a real bat.

Jay Bruce stinks, eh? It is his knee. Check out his
Baseball Reference page, and see that he had an OPS over
.800 4 years in a row. If you can fix the knee, he'd be ripping
the ball. And I'll take his 88-100 RBI over
39 RBIs by my RF anytime. And don't forget: his 10 SB last year were accompanied by 7 CS.

Jon Shepherd said...

Other that that, how was the play, Mrs. Lincoln?

Anonymous said...

Austin Jackson will be playing on the south side of Chicago, "The baddest part of town!"

Roger said...

Jon, I agree that Bruce is a long shot to be who he was but it's possible that the knee was still part of the problem last year. Markakis just hit his first Spring HR. His power might be returning to some extent one year after his neck surgery.

It's possible he is having "limping dog" syndrome where he just won't plant even if the knee is fine. Maybe we could whack him in the other knee to solve it. *smile*

Jon Shepherd said...

A lot of things are possible. I think we just disagree on what is probable.