Wednesday, September 17, 2008

The + is a minus

I've got plenty of reasons to not use ERA+ or OPS+. In a game so full of numerators and denominators, they're pretty quick ways to take already-flawed (and I mean merely flawed, not terminal) metrics and turn them into junk. It doesn't mean I don't understand why Sean Forman's babies are so beloved, and I've got no problem taking a gander.

There is one area of the ERA+ and OPS+ problem that I haven't seen anybody discuss lately, which is that BB-Ref used to not be an in-season resource. Now fans regularly peruse the current season's numbers, complete with ERA+ and OPS+ numbers. The park adjustments used for those are only current through 2007, and BB-Ref's park adjustments are pretty far from the state of the art at this point.

The 2008 Texas Rangers are treated as if they play in a neutral park. The 2008 Los Angeles Dodgers are treated as if they play in a fairly strong hitter's park. How have these teams and their opponents done offensively in these parks as opposed to away from them?

At The Ballpark: .290/.363/.477
Away: .277/.351/.436

At Dodgers Stadium: .243/.305/.359
Away: .268/.336/.409

No pseudo-record is being set this year by the Dodgers' relievers, because those park adjustments are eventually going to eat up the +'s when the 2008 numbers enter the bloodstream. The way I see it, James Loney has had a nice first full season, Kevin Millwood has been just as good as (if not better than) Hiroki Kuroda, and it is insane that Baseball Tonight was trying to hype up Angel Berroa this week (okay, that has nothing to do with this).

I'm not arguing for any particular approach to park factors, but at the very least there are several propagated on BB-Ref that simply don't reflect reality, and I'd rather leave them out of things.

8 Comments:

At 6:04 PM, Blogger Jon Weisman said...

That's fair, but how does one explain how Dodger Stadium went from a hitters park in 2007 to a pitchers park in 2008?

 
At 2:50 PM, Blogger Fifth Outfielder said...

The simple answer is weather (temperature, humidity, wind). Elevation and field dimensions are constants, batter's backdrop and field conditions are more or less constants but can be altered, but weather is pretty heavily variable, and crucially we're not talking just about the weather at Dodger Stadium but the weather at all of the other parks.

Another crucial variable is simply playing time, as the numbers I'm showing (as well as the BB-Ref numbers) aren't designed to scientifically compare hitters at and away from the stadium (Tangotiger's WOWY system tries to do this).

Finally, there is simple variance in performance; if everything about every ballpark stayed the same (weather included), the year to year park factors would still fluctuate.

 
At 4:09 PM, Blogger Paul Scott said...

I don't see your comment on Loney, but I agree on the rest.

Loney has two things this year that I don't think park factors can sufficiently explain:

1. An IsoP of 0.050. That sucks in any park.

2. A FB% of 38%. Even if Park Factors are contributing to his abysmal 6.5% HR/FB%, the fact that he is hitting so few fly balls will mean a lack of power irrespective of park.

We have a 1B that lacks both patience and power. Both could develop. The Park Factors in play, however, don't seem to me to be big contributors to the problem.

 
At 4:10 PM, Blogger Paul Scott said...

FB% of 36%, rather. My typo made him look even better than he is.

 
At 12:58 AM, Blogger Fifth Outfielder said...

FB% has nothing to do with value, so what's the point? And Loney's ISO is ~.150, not .050.

Loney's been about an average first baseman this season. He doesn't look that way if you treat his numbers like they accrued in an offense-friendly run environment. If you want to complain that a 24-year-old is not yet above average or does not have a lot of power or patience, go right ahead, I suppose. I just don't see the point in slagging a player in his first full season for not being above average.

His ISO and Walks/PA are below average by modest amounts. His batting average is well above the mean, which swamps the others. If those aspects of his game improve (patience and power), as they do for the vast majority of 24-year-old professional hitters, then he'll be a pretty valuable contributor and possibly a star at some point.

 
At 8:37 AM, Blogger Paul Scott said...

Sorry, IsoD. Another typo. And the point is that he cannot walk at an acceptable rate.

FB% pretty much directly relates to hitting homeruns, since almost all homeruns are flyballs. The lower your FB%, the higher your HR/FB (obviously) needs to be. Good power hitters will have both a high HR/FB rate and will be hitting more FBs.

And yes, both of these might develop. As you say, typically both power and patience improve and Loney does not have a long way to improve to have average power - especially if he could be a corner outfielder. I am not sure how you conclude that his walk rate, however, is merely "below average by modest amounts." It is well below average. League average IsoD is around .075. His is 0.050 which is near the bottom.

I don't trust bating average and that is 100% of his value right now. One year where his BABIP is below average and he will have almost no value that year.

You talk about him possibly being a star, but I just am not seeing any reason to believe that is possible or likely. It would take huge improvements in patience plus some steady improvement in power.

Does patience improve over time? Every indicator is that it does and that there is no discernible ceiling. But Loney has a very long way to go to even be average in that department. Spending some time (but not too much) I could not find a player who went from IsoD of around 0.050 to 0.090 or more. If they are really outstanding players, nearly superstars, and they start their career at around 0.050 they end up, at best, around league average (0.075). Most don't even do that - and that is the superstars.

I am not writing Loney off. He is an acceptable 1B and is very cheap and young. He will improve (most likely his HR/FB rate will improve and he'll have some power). I will be very surprised if he ever walks at even league average.

 
At 3:35 PM, Blogger Fifth Outfielder said...

Paul, you're throwing out numbers without thinking of their interrelation. Loney does not walk often and does not hit many fly balls, and we both agree on that. I look at it and see that he's got a slightly above average BABIP (.319 vs. NL .297), which you would expect from someone who doesn't hit many fly balls; he strikes out very infrequently, which you would expect from someone who doesn't walk often. It is a combination that yields *sustainable* high batting averages. That does not mean that he is slump-proof, but pointing out that an awful year of BABIP (which, again, is fairly unlikely with so many BIP and so few FB) will send a season down the tubes only means that he, like every other baseball player, is capable of underperforming in a season - he can also overperform.

Loney has 44 BB in 623 PA (7.06%). NL non-pitchers have 8158 BB in 89611 PA (9.10%). Tangotiger has found that an average 24-year-old is about 4/5 of the way to their peak walk rate (http://www.tangotiger.net/agepatterns.txt), which would suggest that at age 37 (peak for BB) Loney would have a league average walk rate *assuming his development of this skill matches that of the study population.*

My point is that Loney is an average player now and we have no reason to think he'll get worse (since a reasonable projection was for him to be about average this season). If he improves his power, he will likely lose some of his contact ability and gain some walks. If he doesn't, then he might just keep being a batting average machine. I'm not saying he is now a star or will eventually become a star, but any pre-arb average position player is a highly valuable asset, and that this one could become a star is encouraging.

 
At 4:05 PM, Blogger Fifth Outfielder said...

Oh, and by the way, I don't understand why you stated that the park factors "don't seem to me to be big contributors to the problem." Of course Dodger Stadium isn't the reason why Loney is not hitting HR or drawing walks. It's the reason why he isn't hitting more singles and doubles; why leave that out of the analysis? Loney is hitting .306/.343/.471 on the road. Of NL 1B, Teixeira, Fielder, Gonzalez, LaRoche, Pujols, and Berkman have better road numbers; Lee, Delgado, CoJack, Votto have equivalent numbers; and Howard, Jacobs, Bowker, and Helton are considerably worse. Considering that there are only five or so good 1B in the AL besides Teixeira, his road numbers fully support the thesis that he's an average 1B. (And his .280/.345/.402 home line in a park where all batters have combined to hit .243/.305/.359 is not exactly evidence that he's no average 1B.)

The other thing to note is that the Dodgers have made no effort to platoon Loney. While it's nice to have a star LHB who is good enough that a platoon is unnecessary, that does not mean that the player should be evaluated based on averaging their contributions when the team damn well should know that it can do better on days when any LHP (not just "tough" ones) are on the mound. A platooned Loney would look more like a star, and depending on the resources used to generate the other half of the platoon, could be much more valuable overall than the Loney-162 we're getting.

 

Post a Comment

<< Home