The Strasburg Shutdown and What We Don’t Know
http://ppt.cc/_B~n
by Dave Cameron - September 10, 2012
On Friday night, Stephen Strasburg took the mound in Nationals Park for the
last time in 2012. Since I live about six hours from DC and I hadn’t seen
him pitch in person yet, I figured I shouldn’t pass up on the opportunity to
see him for myself, so I made the drive up on Friday afternoon. As you’ve
undoubtedly heard, Strasburg wasn’t particularly sharp on Friday, getting
removed after throwing just three innings, and so the Nationals decided that
Friday was his final start of the year, moving his shutdown up one start and
ending his season at 159 1/3 innings.
星期五是Strasburg在2012年的最后一次登板 这场比赛Strasburg不像之前那样主宰
投满三局就被球队换下场 今年他投了159又1/3局
It’s obviously a rather controversial decision, and I’ve advocated for the
position of more aggressive usage, skipping starts and manipulating the off
days to try and make him available for the postseason. Watching him struggle
in his final start didn’t disuade me from believing in the merits of that
kind of approach, and I do think that perhaps there were alternative ways of
handling his workload that might have allowed him for pitch deeper into the
season. However, the unavoidable reality of this situation is that everyone
is dealing with a great quantity of unknown variables, and for any of us to
say that one decision is distinctly better or worse than another is probably
an on overestimation of our own knowledge.
这当然是最争论不休的决定
而我(作者)主张更积极的使用方式: 直接跳过关机 然后让他持续投到季后赛
最后一场的挣扎并无法让我去相信值得如此这样做
而且我相信是有其他的方法来监测他的投球负担 这样可以让他在球季中投的更长
然而事实上不可避免的事实是 有大多大多的变量了
说一个选项是比较好或是坏 很可能是高估了我们的智慧与知识
The secret to keeping pitchers healthy is still perhaps the biggest unknown
entity in baseball, and our ability to predict which pitchers are going to
stay healthy is not much better than simple dart-throwing. As more focus has
shifted to the causes of physical breakdown, workload has gotten more than
its fair share of attention, and efforts to avoid overuse have become far
more commonplace in the last 10 to 15 years. However, even with this focus on
responsible workloads, we haven’t seen a sea change in how often pitchers
are getting hurt.
如何去保持投手的健康至今仍是最大的谜团
我们去预测投手保持健康的能力 事实上并不比射飞镖来的好
近10-15年都在注意避免过度使用投手 但就实际情况 我们并没有发现投手更不容易受伤
Given that pitchers have different physical strengths and weaknesses, it’s
likely that a one-size-fits-all approach isn’t all that useful, and what
might be good for one pitcher could be bad for another. So, while we can say
with some certainty that Strasburg would have been at a higher risk of injury
if he would have thrown 250 innings this year rather than the 160 he actually
threw, we don’t really know where he lies on the reasonable usage spectrum.
You could probably make a case for any number between 160 and 250 and have a
reasonable amount of evidence on your side that the total innings count wouldn
’t be significantly more harmful than any other number in that spectrum.
And, with a knowledge gap that large, it’s just hard to have any kind of
strong opinion about what the right number for Strasburg this season actually
was.
每个投手的身体强度与弱点都不一样 使用同一标准并不是很有用的
当我们说 假设Strasburg今年投250局会比投160局来的更有受伤风险 其实我们不知道
也许可以去蒐集160-250局的投手数据
然后有个合理的证据来证明投更多的局数 其实不是真正影响投手受伤的原因
接着 160-250的局数范围也过大 你也很难去找到这季正确关机Strasburg的局数
The Nationals obviously erred on the side of caution, giving their ace a
number pretty close to the lower bound, and refusing to shift his starts
around to maximize the leverage of those innings. They wanted to allow him to
maintain his regular patterns, and again, this is an area where we simply don
’t know the effects of alternative options. There just isn’t much
historical precedence for this kind of situation, and the uniqueness of each
pitcher’s body limits what we could learn from earlier cases anyway.
国民队明显的对于Strasburg非常小心 在低限度下就让他关机 而且不让他再投更多局数
国民想让Strasburg保持平常的状况 但这又是一个领域 我们基本上不知道这样做有何效果
我们并没有太多的历史资料可以来分析 而
且每位投手的体能都是独一的 这限制了我们的研究
So, the Nationals chose something like the most conservative usage path
possible, but given how little is known about keeping pitchers healthy, their
decision is certainly within the bounds of what one could consider
reasonable. And, of course, health isn’t the only variable in play here.
所以在我们对保持投手健康极小的知识下 国民队做了最保守的方法
As we saw on Friday night, there is some evidence that Strasburg is currently
somewhat less effective than he was earlier in the season, and perhaps a full
season of pitching is starting to catch up with him to some degree. For
instance, take a look at his PITCHF/x velocity chart:
当我们看星期五的比赛中 有些迹象显示Strasburg的表现比季初来的差
我们来看看PITCHF/x的球速表
http://www.fangraphs.com/blogs/wp-content/uploads/2012/09/Strasburg.png
While he has mostly maintained his average velocity throughout the summer,
his peak velocity is down from earlier in the season. In May and early June,
he was regularly getting up into the 98-99 range, but lately, he’s topped
out at 96 or 97. It’s not a smoking gun, but given that velocity tends to
increase as the season goes on, the fact that Strasburg’s fastest pitches
have gotten a little bit slower suggest that there is some legitimacy to the
idea that he’s beginning to wear down.
虽然Strasburg几乎维持了他的火球球速 但他的极速比之前下降一些
在5月以及6月初 球速是98-99 之后则是96-97
这似乎有个合理的解释: Strasburg开始累了
There’s also some evidence of declining dominance in opposing batters
swinging strike rates. In his first start of the season through July 15th —
his first 18 outings — opposing batters only posted a swinging strike rate
below 9% twice, and they were over 13% seven times. In his last 10 starts,
however, he only posted a swinging strike rate over 9% five times, and only
once got over 13%. His command also wasn’t as crisp as it was earlier in the
year, as he walked three or more batters in a game four times in his last 10
starts after doing it four times in his first 18 starts.
另一个现象是Strasburg没有像之前那样的宰制对手
在7/15前 前18位出局数中的挥棒落空率 有两次低于9% 有7次则是高达13%
在最近的10场先发 挥棒落空率有5次高过9% 但只有一次超过13%
另外他的控球也没有像之前那么精准 最近10场有4场投出3次以上的BB
前18场中 只有4次
Early season Strasburg was the most dominant pitcher in baseball, at least on
a per-innings basis. Recent Strasburg has been more human, mixing in some
good starts with some clunkers. If this trend was going to continue, it’s
certainly possible that the gap between Strasburg and Ross Detwiler in
October wouldn’t be so large that swapping them would result in a huge
change in expected outcomes. In fact, you could argue that the outcome
differences now aren’t even that large.
季初Strasburg是主宰比赛的投手 但现在他比较像人类(几场投很好 几场挣扎)
如果他持续这种表现 那Strasburg跟Detwiler的差距就没有之前那么大
Strasburg’s posted a 2.82 xFIP this year, just about 1.50 runs per nine
innings better than Detwiler this season. Strasburg’s posted higher than
average BABIP and HR/FB rates, while Detwiler has been below average at both,
so you might want to adjust that gap down slightly to account for the fact
that there might be some difference in skills in those FDP areas. So, maybe
the gap is 1.25 runs per nine innings instead. That’s certainly a big
difference, but we also have to remember that October baseball is not the
same as regular season baseball, and that managers can be much more
aggressive in their bullpen usage in the playoffs. Given how deep Washington’
s relief corps is, it’s unlikely that either pitcher would be asked to go
beyond six innings, and five is probably more likely against a good offensive
opponent. So, instead of 1.25 runs, we’re probably dealing with something
closer to 0.7 runs per start difference.
Strasburg这季的xFIP是2.82 大概每九局比Detwiler多守住1.5分
他的BABIP跟HR/FB高于平均 而Detwiler则是低于平均 调整以后两者差距大概是1.25分
事实上差距还是相当大 但请记得季后赛跟普通球季不同 教练通常会更加使用牛棚
以国民队的牛棚深度 大概很难会让先发投超过6局
以每九局多失1.25分来看 最后很可能是多失0.7分
And that’s using Strasburg’s full season line. If you think he’s wearing
down, maybe he’s more of a 3.25 xFIP guy going forward, and that would push
the difference more towards 0.5 runs per start. Don’t be fooled by those “
ERA since the All-Star break” graphics that say that there’s no drop-off
here, but a half run gap isn’t overwhelming, especially if you think that
the trade-off is getting a healthier Strasburg for the future.
如果使用Strasburg整季 外加目前持续疲累的程度 xFIP可能是3.25 大概是每场多丢0.5分
别被明星赛前后的ERA变化图表给骗了
And then, of course, there’s the significant variance around player
performance in small samples to begin with, and we’re not just talking
Strasburg and Detwiler here. There’s a real chance that the playoff games
that Strasburg would have pitched in wouldn’t have been close enough to be
decided by the quality of the starting pitcher anyway. If we built a
histogram of the potential outcomes of any Strasburg playoff start, there
would be a tail on one end that represented a blowout by the Nationals, in
which they could probably roll out any pitcher they wanted and still win the
game. Likewise, there would be a tail on the opposite side of the spectrum
that represented a dominating performance from the opposing starter so that
even a great performance by Strasburg would still result in a loss.
[这整段其实是废话 作者说季后赛样本小 变化很大 小史可能会投不好
交给其他投手说不定更会赢 然后如果小史投的好也不一定会赢 因为对方投更好...]
The starting pitcher is an important factor in the end result of a ballgame,
but it isn’t the deciding factor, and it’s certainly possible that the
decision to use Detwiler instead of Strasburg ends up not having much of an
effect on the Nationals playoff chase at all, simply due to outcomes that
have nothing to do with the quality of each pitcher. Combine that with the
volatility of projecting Strasburg going forward, the huge unknown that is
pitcher injuries and reasonable workloads, and the fact that the Nationals do
have a good team even when Strasburg’s not on the mound, this decision by
the Nationals is certainly defendable.
虽说先发对比赛影响很大 但不是决定性因素
就算小史停机也对国民队进军季后赛的影响不大
结合预测小史的外来表现,未知的受伤风险及合理的工作量 将小史停机是相当合理的
况且国民没小史也是好球队
It’s not the only defendable decision that they could have made, but this is
an area where it just doesn’t make much sense to take a strong stance one
way or another. There are so many unknowns that the best thing we can do is
admit that we don’t know enough to have a strong opinion either way. The
Nationals are doing what they think is in their franchises best interests,
and they very well may be right. They may also be missing a chance to take a
deep playoff run, and the reward that comes from that kind of run might be
worth the extra risk. There are a lot of maybes here. When there are this
many questions that we just don’t have the answers to, the best thing we can
do is acknowledge where our limits are. On handling Stephen Strasburg, we
just don’t know enough to say whether any one decision is better than
another. The Nationals made a decision and stuck with it. That’s probably
all they could have done.
有太多未知的事情导致我们无法做出最好的选择
国民也只是做出他们认为对球团最大的利益选择 而且他们很可能是对的
他们或许会错失一些打入WS机会 这有可能超出所估计的额外风险
但是有太多的如果与假设了
我们能做的最好的事情就是知道我们的限制在哪
在Strasburg的例子中 我们无法说哪些是更好的决定
至少国民队做出了最终决定而且执行它