Yesterday, I posted this article about the Texas Rangers offense, and how the numbers show that they aren’t the elite offense that everyone claims they are. The purpose of the article was to say just that, and nothing more. I simply wanted to challenge everyone’s preconceived notions about how the Rangers were winning. There was also the other, unwritten, side that most people didn’t seem to pick up on; namely, that their pitchers are much better than they’re given credit for.
Amongst all the hate mail from Rangers fans, (Which I loved! It was very entertaining.) there were 2 legitimate criticisms of my article, and I’d like to address them, with numbers. The first is that I probably shouldn’t have used wRC+ as the basis for my article. I like the fact that’s it’s normalized to 100, and thus is makes comparing the numbers easier. It’s easy to tell how big of a difference there is, as opposed to, say, wOBA. There is a built in context to wRC+ that just isn’t there for non-normalized statistics. I do try to write so that all fans can understand what I’m trying to say, and not just those well versed in the new metrics.
This was a poor choice on my part because Fangraphs claims that wRC+ is park adjusted, and it is, sort of, I guess. Yes, there is a “park adjustment” factor, but it is a very tiny adjustment and it is done after the fact. wRC+ is based on wOBA, which is not park adjusted. Ultimately, the adjustment is poorly done analysis. I could go through the mathematics to show you this, but that would be painfully boring for both you and I. So I won’t. Instead I’ll just redo my tables using wOBA, and other stats, which I should have used in the first place. Besides, the the point was about how much the Ballpark in Arlington effects players’ stats, not how the quality of the ballpark adjustment in wRC+.
The second criticism was that I should have provided better context of the rest of the league. Only including Colorado was a mistake. There’s a possibility that all teams home/away spits are quite large (they’re not), and I didn’t address this potential variable. In my defense, I did think of that, and I just made the incorrect decision to ignore that for the sake of keeping my article on the short side.
Tables, numbers, data and math after the jump. Also words, many many words.
|Team||wOBA away||wOBA home||Difference||Adjusted|
As you can clearly see, the Rangers have by far the largest home/away difference of any team in the American League. As one very astute reader pointed out, most teams hit better at home than away. The average difference between a team’s home and away splits is 0.0112. The 4th column adjusts for that difference so we can better compare all the teams.
The results are exactly what one would expect if you consider the parks teams play in. The Rangers’ difference is by far the largest, almost exactly double that of any other AL team. Still don’t think their park seriously inflates their offensive numbers?
The only real surprise on that chart is our own Seattle Mariners. I expected the M’s to be at the very bottom of the chart with numbers similar to that of the Rays. I’m guessing that when you’re as bad offensively as the M’s it doesn’t matter what park you play in, you still wont be able to hit, and thus the difference gets lots.
The league average wOBA is .321. Adjusting the Rangers’ road wOBA to account for half of the league wide home/away difference (half because the other half should be applied to the home split) gives a result of .320. Almost exactly the league average. Let that sink in for a second. Without their ballpark factors helping them, the Ranger’s offense is right at the league average.
Don’t like wOBA? how about OPS:
|Team||OPS away||OPS home||Difference||Adjusted|
The results are almost identical as they were for wOBA, which is what we’d expect. I just didn’t want you to think I was cherry picking stats that show’d a difference that wasn’t there on other stats. Clearly the Rangers’ offensive numbers are getting an incredible boost from playing in that ballpark. And in case you were wondering, the league average OPS is .728. Adjusting the Rangers’ road OPS to account for the standard home/away difference, you end up with .722, which is below average, but only slightly so.
The biggest problem with this so far is that single season home/away splits can vary by quite a bit. Remember that each team only plays half their games at home, so we’re talking about a comparing 2 half-seasons with each other, and this season isn’t over, so it’s actually less than that. So to make sure this isn’t simply a case of small sample size variation, let examine the past 5 seasons together, from 2006 through the present:
|Team||wOBA away||wOBA home||Difference||Adjusted|
Once again the Rangers are at the top of the list with the largest difference between home and away performance, and once again, it’s almost double that of the next team on the list. I think we can put to rest that this is simply a case of a one season aberration. Oh, and in case you were wondering, I went back to wOBA since it’s a better, more accurate assessment of offensive performance.
Also worth noting is that when you look over 5 year’s worth of data, there’s Seattle down at the very bottom where we’d expect them to be. Examining how badly Safeco Field hurts Mariners hitters, and helps their pitchers, is a topic for another post.
Now, I’m going to reiterate what I said in the opening paragraph. I’m not trying to simply “spew hate” on the Texas Rangers. I’m simply trying to challenge the preconceived notions everyone has about them. The data suggests very strongly that they are not the elite offensive team that everyone thinks they are. They are also not as devoid of pitching as everyone thinks either. Remember that both teams play in that ballpark during their home games, meaning the other team gets an offensive advantage as well, and that in turn hurts the stats of the Rangers’ pitchers.
|Team||FiP away||FiP home||Difference||Adjusted|
While the data isn’t as dramatic on the pitching side of things, the trend is still there. Notice which team on top? It’s the Rangers of course, but it would be very difficult to believe that it wouldn’t be, after looking at the offensive data. Everything that is working to making their hitters look better than they are is also working against their pitching staff.
If you made it this far down the page. I’d like to thank you for taking the time to read all that. It was quite a lot, and much more than I had ever intended to write on the subject. I hope that you came away from this recognizing just how much of an effect park factors can have on the stats of a baseball team. The Rangers’ offense clearly isn’t the elite force they’re made out to be. They are a much more average club than you’ve been led to think. Pitching wise, they’re much better than everyone wants you to believe.
This doesn’t mean they are in any way not a good baseball team. Clearly they are. They are the defending AL campions and are currently leading the AL West. So to all of you Rangers fans who are reading this, you can put down your torches and pitchforks… please…