And, for some actual baseball news, the M’s have reacquired Aaron Looper. That didn’t take long. They swapped out Glenn Bott, last ranked 39th on the Future Forty. Bott has average stuff across the board with decent movement, and the best thing he has going is that he’s a southpaw. The organization has never liked him since he’s had a few run-ins with pitching coaches over the past several years. He was the definition of an expendable part. Not that there’s any room for him in Tacoma, but I’d certainly rather have Looper than Bott in the organization.
Continuing with the XBH/BIP stuff from below, I ran some correlations between different statistics to determine the usefulness of the metric and to see if there were any interferences from groundball/flyball tendencies. As a basic primer to correlations, 1.00 would be a perfect correlation, meaning that the results from each category mirror each other. The closer the decimal gets to 0, the weaker the correlation. A negative correlation means that the inverse is true; as one category rises, the other falls, and vice versa. Anything above .5 (or below -.5) is considered a moderate correlation, above .8 (or below -.8) would be a strong correlation, and anything in between -.5 and .5 is considered weak. Anyways, results below:
Correlation between XBH/BIP and GB/FB ratio: -.01.
In other words, there is no correlation whatsoever, and the two numbers have almost nothing to do with each other. The Dodgers GB/FB rate of 1.54 was the highest in the majors in 2003. The Mariners mark of .95 was lowest in the majors. Yet, they still managed to come in 1-2 in XBH/BIP. It does not appear that a team’s tendancy to induce large amounts of ground balls or fly balls has any impact on their performance in giving up extra base hits.
Correlation between XBH/BIP and ERA: .69
This is a moderate correlation, meaning that teams who generally do well in preventing extra base hits also generally do well in preventing runs, but there is a pretty sizable margin of error. Considering this stat completely ignores the effects of home runs, walks, and strikeouts, thats to be expected. For simply attempting to isolate one aspect of defense, it correlates quite well with how well a team keeps runs off the board.
Correlation between strikeouts and ERA: -.63
Team strikeout rates are moderate correlations to run prevention as well. There’s a lot more to defense than making the batter swing and miss, but it’s clearly a good thing.
Correlation between walks and ERA: .38
Throwing strikes helps, but keeping a low walk rate does little to insure that your team will prevent runs.
Correlation between home runs and ERA: .83
Home Runs are bad. If you give up a lot of them, you’re likely not going to have a very good ERA.
Correlation between OPS allowed and ERA: .97
That’s about as strong a correlation as you’ll find anywhere in the game. Pitchers with low OBP/SLG allowed will have low ERA’s. Pitchers with high OBP/SLG allowed will have high ERA’s. If you’re interested, the correlation between OBP and ERA is .945, while SLG and ERA is .952. Despite what Michael Lewis wrote in Moneyball, OBP is not anywhere near three times as important as SLG.
Basic conclusions:
XBH/BIP is a decent judge of outfield team defense and is not affected by ground ball/fly ball rates. Park factors not withstanding, it is apparent that the M’s pitchers have benefited tremendously from the trio roaming the outfield the past three years, and it is likely that the entire pitching staff has been somewhat overrated in local circles. To kick a dead horse one last time, it is apparent that Ryan Franklin has been bailed out by his defense more than any other pitcher in baseball, and his transformation into a pumpkin in 2004 will have almost nothing to do with his abilities and everything to do with his teammates.
Proof that our readers are smarter than we are. This showed up in our inbox from Anthony Passaretti:
Reading your post today on refining the extra base hits study, there is still
one more step to go. You mention that Seattle’s outfield defense comes out
slightly ahead of LA’s when looking at BIP, but is that really accurate?
Consider their flyballs:
Seattle: 1843
Los Angeles: 1273
That makes a heck of a difference. When the Dodgers traded Kevin Brown to the
Yankees, there was something on Baseball Prospectus about the percentage of
1B/GB. That inspired me to grab the numbers off ESPN.com to look at singles
per groundball, and doubles & triples per flyball. Looking at it that way,
Seattle comes out WAY ahead.
The league average for doubles per flyball was 18.1%. Seattle was first at a
psychotic 11.9%. In comparison, Anaheim was second at 14.5%. Texas was last
with a 21.4% mark. For triples, the league average was 1.9%. Seattle was again
well ahead at 0.8%, Minnesota second at 1.3%, and Colorado scored last with
2.8%.
The net result is Seattle is 135.3 extra base hits above average. Anaheim is
second at +71.1. Imagine that. Even the second best team in the majors was 64
gap hits behind. Texas was last in the majors at -59.6.
If we adjust all teams to the same number of flyballs, Seattle is +119.2,
Anaheim still second at +64.6, and Boston takes over last at -61.1.
It’s interesting to note that the top 3 teams in XBH/FB (Seattle, Anaheim,
Minnesota) were also the bottom 3 teams in 1B/GB. Of course, the fourth best
in the former (Oakland) was also the second best in the latter, so the
relationship isn’t perfect. Boston also did very well in 1B/GB, which is
baffling considering the presence of Todd Walker. Take from that what you
will.
Oh, and this year? Seattle has given up 23 doubles on 66 flyballs–three times
higher than their 2003 rate.
On the bright side, they haven’t given up any triples yet. So they’ve got that
going for them. Which is nice.
-Anthony
This isn’t the final say-so, either. For a perfect result, we’d really have to include park factors (which I’m assuming really help both the M’s and Dodgers and hurt the Rangers) and look at more than one year. But goodness, that gap is just huge, and I don’t think any park factor is strong enough to create the illusion that the M’s outfield defense last year was staggeringly awesome.
A few days and a lot of emails from smart readers later, and I’ve realized there were two big flaws in the conclusions I presented based on the extra base hit data from Saturday:
1. I assumed that all plays that weren’t extra base hits were turned into outs, which is obviously not true, as a good amount of the differences were likely from outfielders holding a runner at first and turning a double into a single.
If there’s a good way to figure out how often this occurs, I don’t know of it, so we’ll just call this a gray area that forces us to be less conclusive in our determinations about the exact effects of outfield defense. Turning a double or triple into an out is a lot more valuable than turning it into a single, so without knowing this, we can’t measure what the impact is completely, but I still feel that we can get ourselves in the ballpark with an estimate.
2. I used batters faced instead of balls in play, ignoring the effects of walks, strikeouts, and hit by pitches.
The second problem was a pretty easy fix, so I’ve rerun the numbers as a formula of (doubles + triples)/(batters faced – walks – strikeouts – home runs – hit by pitches). We’ll just call it XBH/BIP, which is short for extra base hits divided by balls in play. The numbers didn’t change much, which isn’t really surprising, but they did change a little bit. I maintain that this is a good, but not perfect, proxy for measuring outfield defense. The results are below, with rank in runs allowed in parentheses:
2001
Best: Oakland, 5.6 percent (3rd)
Mariners: 6.5 percent, 4th best in MLB (1st)
League Average: 7.4 percent
Worst: Texas, 9.4 percent, (30th)
2002
Best: Anaheim, 6.1 percent (4th)
Mariners: 6.8 percent, 9th best in MLB (11th)
League Average: 7.3 percent
Worst: Texas, 8.6 percent (27th)
2003
Best: Seattle, 5.4 percent (2nd)
League Average: 7.3 percent
Worst: Texas, 8.6 percent (30th)
By this metric, the M’s outfield defense was slightly better than Los Angeles’ last year, and the best of any team’s performance from their three gloveman in the past three years. The difference between the Mariners and Rangers last year was 154 doubles + triples. Even assuming that a decent amount of those were singles that the M’s prevented from reaching the gap, that is still an absolute ton of outs, and shows how big of a difference outfield defense can make.