http://tinyurl.com/4xo2fj
by Josh Kalk
April 15, 2008
The Royals' Brian Bannister is off to a tremendous start for the Kansas City
Royals. I mentioned him in my last article, saying that not a lot of people
thought he could repeat his excellent season last year. The main reason was
that he wasn't striking out enough batters compared to the number he walked.
Last year, his ERA checked in at a cool 3.87 but his FIP was a more mediocre
4.52. This is mostly from his K/G being a mere 4.4 and his BB/G of 2.5. Now
2.5 walks per game isn't bad at all, but only 4.4 strikeouts generally is going
to lead you into danger. So how has he turned it around this year so far?
Well, first he has kept his walk rate at 2.5 BB/G but has upped his strikeouts
to 6.5 per game. That is a huge increase and while he probably shouldn't have
an ERA under one, his FIP is an excellent 2.59 so far. His microscopic ERA of
0.86 has certainly been helped by a Defensive Efficiency Ratio of .825 behind
him and a LOB percentage of 81.2 While both of these numbers will cool off, he
still could be one of the better pitchers in the majors if he can keep the
strikeouts coming.
So how has he increased those strikeouts? Well, let's take a look at his
PITCHf/x data and see. Here are the raw data straight from Sportvision and
MLBAM.
皇家队的年轻投手Brian Bannister开季表现优异，我在之前的文章曾经提过很多人对
Bannister今年的表现不是很看好，因为他去年的K/BB值不是很优异。那么，他今年是怎么
投出这样优秀的表现？
来看看数据吧。去年他的ERA是3.87但FIP是4.52，这是因为他的K/BB为4.4/2.5。然而，今
年他将这个数值提升到6.5/2.5，这是相当大的进步。虽然说现在他惊人的0.86 ERA有部份
是因为队友帮忙和极高的残垒率，但他的FIP是2.59，表示即使去掉运气的因素，他仍旧会
是联盟中最好的投手之一，如果他可以维持他的三振能力的话。
所以，他是怎么提升三振的？我们来看看他的PITCHf/x data吧。
Wow, that is all over the map. MLBAM has him throwing four different fastballs,
a slider and a curve. Clearly, a few of these are grouping errors. This isn't
too surprising; analyst Dan Fox has mentioned they are still working out the
kinks to the pitch classification system.
哇，看来他会七彩变化球！MLBAM显示他有四种速球、滑球，还有曲球。当然，有些数据是
有误差的，毕竟这个系统才刚开始运作，还有许多要修正的地方。
First, let's look at the splitters. While Bannister says he would like to
throw a splitter, I haven't read or seen anything that makes me believe these
are really split-fingered fastballs. They are more likely change-ups, as they
are in the same location as the change-ups he was throwing last year.
先来看splitters吧。虽然Bannister曾说过他认为splitters是很好用的球路，但我觉得这
些数据上的splitters看起来比较像他去年在投的change-ups。
Next, what about those cut fastballs? Bannister's four-seamer lives right on
the edge of being a cut fastball, breaking only 1.84 inches towards a
right-handed batter compared to a ball thrown without spin last year. A good
cut fastball has about the same break, but in the opposite direction, so while
I believe these are truly four-seam fastballs, a few had a little more (less?)
break on them and were classified as cut fastballs. This is one of the problems
with classifying pitches individually instead of grouping them together.
Pitchers who throw a certain pitch that is on the border between two pitches
will most likely be shown as having thrown some of each.
那cutters呢？右上角有些Bannister的速球被归类为cutter，但仔细观察可以发现它们的
水平位移却和一般的cutter相反，我认为这些球路其实只是四缝线速球，只是因为break太
大(小?)而被归类为cutter。
Next, let's look at the curveballs that have negative horizontal movement
compared to a pitch thrown without spin. These are somewhat disconcerting
pitches because they are moving like a lively screwball would move. Bannister
didn't throw anything like that last year, and what is worse all came in his
start in Detroit. While the PITCHf/x cameras are supposed to be calibrated
better this year, it looks like maybe Detroit's cameras weren't having a great
day. For now, I'd keep them considered as curveballs and assume that they
really aren't breaking in to a right-handed batter.
接下来是曲球。有些曲球有负的水平位移。这里有一些没有被正确辨识的球路因为它们的
尾劲看来像screwball。Bannister去年从没投过这种球，而且这些球全部都是来自对老虎
的那场比赛。看来原因是那天老虎球场的相机运作得不太好。
Last, what about the group of fastballs way over to the left that are being
classified as about half sinkers and half fastballs? This is a very interesting
set of pitches and deserves closer attention.
最后，我们来看看左侧那些速球吧。这里一半是sinkers一半是fastballs？
First, it is important to note that while Bannister also didn't throw any
pitches that looked like this last year, these appear to be real—he threw
several of these pitches in each game he played. This makes it much less likely
that they are due to camera error. So, assuming they are a new pitch, are they
really two seamers (sinkers)? Last year in spring training, Bannister mentioned
that he was working on a two-seamer, but my classifcation algorithm didn't find
any two-seamers last year. It is possible he started using this pitch before
the PITCHf/x cameras were installed and then scrapped it by the time they were
turned on. I can't find any mention of him working on that pitch this spring ,
though.
看来这并不是相机的问题。虽然说Bannister去年也没投过这些球，但这些球路在每场比赛
都有出现。所以，它们是sinkers吗？Bannister去年春训时有说过他要练sinker，但我在
去年的资料中没有找到他有投过sinker的数据。也许是他在相机装设前就有用过sinker，
但在之后却渐渐不再使用。今年春训也没有听说过Bannister要加强这项球路。
I don't think these are two-seamers. First, their vertical movement is around
10 inches, compared to a ball thrown without spin. While some pitchers do have
large vertical movement with their two-seamers, it is rare. Second, he is
throwing this pitch at 89 mph, nearly two mph faster than his regular fastball.
Almost always, when a pitcher throws both a four-seamer and a two-seamer, the
two-seamer is a couple of mph slower than the four-seamer. So if this pitch
isn't a two-seamer, what is it?
我不认为这些是二缝线球。这几球的垂直位移高达10 inches，只有很少数人投的出来。而
且，这几球球速也高达89 mph，甚至比他的四缝线球还快。所以，这些应该不会是二缝线
球，吧？
I believe it is just his regular four-seam fastball thrown at a different arm
angle. Here is Bannister's release point by pitch type. I have changed all the
cutters to fastballs and splitters to change-ups, and I am listing all these
new pitches as sinkers on this plot to separate them from the fastballs.
这些应该只是普通的四缝线球，只是出手角度的不同。这里有Bannister出手角度的图表
，我已经把之前仪器的错误纠正过来，把cutter调整为fastball、splitter调整为
change-up。
You have to look closely because they are being hidden by some change-ups, but
all these new pitches are being thrown at an angle more side-armed than his
regular release point. A more side-armed release point would impart more
horizontal movement and less vertical movement on the pitch while keeping the
speed about the same. This is exactly what we see here. So I think these
pitches are four-seamers thrown at a different arm angle.
你可以发现，那些sinkers的出手角度和一般的fastball是有些不同：出手角度较低。较低
的出手角度会造成水平位移的增加，这就是我们在图上看到的。
When we break the pitches up this way, we see that Bannister throws at this new
arm angle early in the count, then uses the regular fastball much more later.
In fact, on two-strike pitches he is throwing his regular fastball nearly 60
percent and many of them appear to be up in the zone. This is in contrast to
last year, when he used his slider often to try to put away hitters. If this is
his new strikeout pitch, it will be interesting to see if the league adjusts.
If so, will he then readjust and go back to the slider?
我们可以发现，Bannister对决时会先用这些新品种的速球，接下来才是平常的速球。事实
上在两好球之后一般速球的使用率高达60%，并且落在球带的上缘。然而，去年他在两好球
之后比较常用滑球来引诱打者。如果这项改变是他三振提升的秘密，那打者能去适应这项
改变吗？如果可以，那Bannister的配球会回到原本的模式吗？
Speaking of the slider: Both this year and last, Bannister has thrown a very
hard slider—again, a pitch very close to being called a cut fastball. It is
strange to see a pitcher who throws most of his fastballs in close relation to
his sliders. Because both of these pitches are close to a cutter, the
difference between Bannister's fastball and slider is much less than it is for
most pitchers.
关于滑球，从数据中我们可以发现Bannister的滑球和cutter的变化很接近，这表示他的滑
球的品质和一般的投手比起来并不太好。
It is possible that this is why Bannister wasn't having much success putting
away hitters with his slider. Even if they were fooled and guessed fastball, it
wasn't too much of an adjustment to reach the slider. With the introduction of
this new arm angle, the difference between this fastball and his slider is huge
and something else for the hitters to be thinking about.
我们可以试着做出这样的结论：Bannister的滑球变化不够好，因此很难用滑球解决打者。
然而，他今年调整了某些速球的出手位置，这项改变让他的滑球看起来变化较多，因此更
容易借由速球和变化球的差别来解决打者。