Archive for Research

The Good News About Corey Kluber on Short Rest

By the time a pitcher gets to October, his body and his mind are headed in different directions. The head can’t stop racing, but the body is battered by six months’ worth of battle. That probably seems intuitive, but it’s actually relevant tonight in a very concrete way: Cleveland right-hander Corey Kluber is once again going to climb the mound on short rest, with body and mind at odds. Here’s the good news for Indians fans, though: while the results of postseason short-rest starts isn’t great, the process — which is to say, the movement and velocity recorded on pitches — suggests that adrenaline trumps all when it comes to postseason ball.

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Why Josh Tomlin Gives Up Homers

Right-hander Josh Tomlin starts for Cleveland tonight in Game Three of the World Series. While he does a lot well, he also has a weakness — namely, that he gives up more homers than the average pitcher. It’s possible that, among the explanations you’ll hear regarding that weakness, most will relate either to how it’s because Tomlin lives in the zone or never gives in or something along those lines. He certainly doesn’t walk people, so there would seem to be some logic to that argument.

It’s also tempting to point to the relationship between his walk rate and his home-run rate because of the extremes he’s reached in both departments. Record-setting extremes, actually. This year, Tomlin gave up 16 more homers than he did walks. In over 5200 qualified starting-pitcher seasons since World War II, nobody has ever produced a greater discrepancy in that department. Only four times — Carlos Silva in 2005, Brian Anderson in 1998, Brad Radke in 2005, and then Tomlin this year — has that difference run into double digits.

Still. The walk rate is nice. And it’s probably not why he gives up homers.

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Why the Front-Door Sinker Isn’t a Trend… Yet

It may be impossible to believe after the last two games — after all the front-door sinkers thrown by Corey Kluber that turned the Cubs’ bats into mush and after a similar experience last night facilitated by his apprentice Trevor Bauer — but the front-door sinker is not a hot new trend in baseball.

First, to review: the front-door sinker is thrown from a pitcher of one hand to a hitter of the opposite one. The intention? Essentially, to fake the batter into not swinging. It’s a sinker thrown at the hip that then moves into the strike zone. Here’s an example from August Fagerstrom’s piece on Kluber this week:

Seems like a rad pitch. In the era of the swinging strike, it’s a pitch that’s designed to elicit a take. It relies on command in an era when we wonder if pitchers even have any command. After all, as I noted in my for last year’s Hardball Times Annual, the average pitcher misses the catcher’s target by more than 11 inches on a 3-0 count.

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How Should We Evaluate a Manager?

I’ve got a vote for American League Manager of the Year this season and I’m terrified. My first vote as a member of the Baseball Writer’s Association, and it’s the impossible one.

Maybe impossible is too tough a word. I’m sure I’ll figure something out in time to submit a vote. But evaluating the productivity of a manager just seems so difficult. We’ve seen efforts that use the difference between projected and actual wins, or between “true talent” estimations for the team and their actual outcomes. But those attribute all sorts of random chance to the manager’s machinations.

I’d like to instead identify measurable moments where a manager exerts a direct influence on his team, assign those values or ranks, and see where each current manager sits. So what are those measurable moments?

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Is Oakland’s Mount Davis Killing Fly Balls?

My favorite part of my job is when players ask me questions. It’s difficult enough to come up with questions on a daily basis, so it’s great to get a free piece — and it’s even better when the question came from someone who plays the game every day. Once you make it to the Show, it’s all about staying in the Show, and that means making the most of your athletic talents. Strategy is often the key component to these questions.

When Athletics infielder Jed Lowrie came bounding across the Oakland clubhouse to me with his question earlier this year, he’d already decided to act on what he had perceived as an issue with his new/old home park. In the spring, he’d connected with his hitting coach, Darren Bush, in order to work on going the other way since he was leaving Houston’s friendly confines for Oakland’s cold. Because fly balls die in Oakland, and opposite-field fly balls are, by nature, less damaging than their pull counterparts, part of that new “oppo” approach was a heavier ground-ball profile. Mission accomplished.

But the reason behind Oakland’s fickle fly-ball play was still on his mind. “I think it’s Mount Davis,” he said back then. His theory was that the wall-like 10,000-seat expansion in center field — constructed in 1996 and nicknamed Mt. Davis in scorn after the Raiders’ late owner Al Davis — was responsible for suppressing fly ball distance in the Coliseum.

Answering his question turned out to be fairly difficult.

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A Long-Needed Update on Reliability

It’s been over a year now since Sean Dolinar and I published our article(s) on reliability and uncertainty in baseball stats. When we wrote that, we had the intention of running reliability numbers for even more statistics, including pitching statistics, of which we had included none.

That didn’t happen. So a little while ago, when I was practicing honing my Python skills by rewriting our code in, well, Python (it was originally in R), I figured, “Hey, why not go back and do this for a bunch more stats?” That did happen. Sean was/is swamped making the site infinitely better, though, so I was on my own rewriting the code.

In case you need a refresher, never read our original article, and/or don’t want to now, here’s a quick description of reliability and uncertainty: reliability is a coefficient between 0 and 1 that gives a sense of the consistency of a statistic. A higher reliability means that there’s less uncertainty in the measurement. Reliability will go up with a larger sample size, so the reliability for strikeout rate after 100 plate appearances is going to be much lower than the reliability for strikeout rate at 600. Reliability also changes depending on which stat is being measured. Since strikeout rate is obviously a more talent-based stat than hit-by-pitch rate (well, maybe not for everybody), the reliability is going to be higher for strikeouts given two identical samples. You can think of it like strikeouts “stabilize” quicker than hit-by-pitches.

Reliability can be used to regress a player’s stats to the mean and then to create error bars around that, giving a confidence interval of the player’s true talent. To continue with the strikeout example, I’ll add another point — namely that, the more plate appearances a player has recorded, the closer the estimate of his true talent will be to the strikeout rate he’s running at the time. In fact, strikeout rate is so reliable that, after a full season’s worth of plate appearances, a player’s strikeout rate will probably be almost exactly reflective of his true talent. The same cannot be said for many other stats, like line drive rate, which is mostly random; the reliability for LD% never gets very high, even after a full season’s worth of batted balls.

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How to Think of Postseason Contention, Elimination

We’re at that time of the regular season during which most teams are making a final push to clinch a spot in the postseason. Some teams (such as the Cubs) have basically already clinched a spot and some others (such as the Twins) are already mathematically eliminated. Most teams fall somewhere in between.

Many baseball fans will look at the standings every day in September. If they see their favorite team is leading its respective division, they’ll hope that, for the rest of the regular season, that team win will more games than anyone else in the division, thus allowing that team to become the division champion. This is guaranteed.

If they see, on the other hand, that their favorite team is not leading its respective division, they will check the number of games remaining and the number of games by which their team is behind the division leader. If the number of games remaining is greater than the number of games behind, then they can hold out hope that their team can win the division by winning all its remaining games, while the division leader loses all their remaining games. Unfortunately, this is not always guaranteed.

The type of error is made not only by Average Joe sports fans, but also professional sportswriters.  This article will describe these tricky scenarios in which teams are eliminated from postseason contention.

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Dave Dombrowski Has Been Good at Trading Prospects

Know this — Dave Dombrowski likes to make trades. He was first named a general manager back on July 5, 1988, assuming the title of “youngest GM in the game” back before it was cool with the Montreal Expos. He made his first trade on July 13. His aggressive nature was sometimes just off center stage, as the teams he had previously helmed — the Expos, Marlins and Tigers — have rarely been media darlings. But now he is running the Red Sox, and they get plenty of coverage. While that level of coverage might not be fair or warranted, his deals are being scrutinized hard these days. Is he gutting the farm system? Or does Dombrowski know how to pick ’em? I thought I’d take an objective stab at his trade record.
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Tommy John Surgeries: 2016 Update

It’s no secret that, over the last few years, the number of Tommy John surgeries has increased across all levels of baseball. As we emerge from the All-Star break, let’s take a snapshot of the current state of Tommy John surgeries at the professional ranks.

New Tommy John Surgeries
Let’s start with some good news. The number of Tommy John surgeries at the major-league level is down in 2016 compared with the last couple of seasons. Comparing totals at this point in the season over recent years, there have been fewer Tommy John surgeries to date this year than any since 2011.

MLB Tommy John Surgeries, By Year
Year MLB TJ Surgeries
2016 12
2015 20
2014 24
2013 15
2012 26
2011 8
2010 6
2009 17
2008 8
2007 12
Surgeries before July 12 of each year

In the past five seasons, I’ve attempted to track Tommy John surgeries at the minor-league level more closely than in prior years. This information is much more difficult to collect, and certainly there will be many surgeries missing from the list every season. Looking only at surgeries known to have been performed by this time in the year, however, the 2016 campaign looks more like 2012-2013 than the last two years where surgery counts had spiked.

Known MiLB Tommy John Surgeries, By Year
Year Known MiLB TJ Surgeries
2016 38
2015 60
2014 63
2013 44
2012 39
Surgeries before July 12 of each year

So the most interesting question here is: has something actually changed to cause the number of Tommy John surgeries to drop this year compared with the last two seasons?

I can’t say that I know the answer, but I suspect it’s due to a number of factors.

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Are Veterans Better at Slump-Busting?

Way back at the winter meetings, Brad Ausmus said a thing that I found interesting. It’s stuck with me ever since, gathering moss as I’ve pondered it occasionally. But by itself, it raised my eyebrow and set me on a path.

“Especially hitting,” began Ausmus. And continued:

[W]henever you recover from a struggle or go through a slump, you fall back on that experience anytime it happens again. That’s absolutely true. I can tell you that from experience. That’s why veteran players are much better equipped to handle slumps than young players just because of the experiences.

There’s a lot to unpack here, but before we ask the players and the numbers, I thought it would be interesting to call back to a psychology experiment with which I once assisted in college. In a study colloquially called The Beeper Study run by Laura Carstensen at Stanford University, we found that getting older led to more emotional stability and happiness.

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