http://tinyurl.com/5d3jf9 by Jeff Sackmann April 17, 2008 Baseball's conventional wisdom suggests that batting eighth in the National League—that is, in front of the pitcher—has its pros and cons. With an extremely weak hitter on deck, opposing pitchers would seem less likely to throw strikes. To a patient No. 8 hitter, this is a benefit: He can simply wait it out and take his base. Less-patient hitters, however, can end up swinging at bad pitches. There has been more talk than usual in 2008 about managing the pitcher's spot in the lineup. This week, the Cardinals and the Brewers are facing off in St. Louis, and both Ned Yost and Tony LaRussa are slotting their pitcher in eighth. In this case, the wisdom about batting eighth must be shifted to the No. 7 spot, which may mean that a better hitter (in the case of the Brewers, J.J. Hardy) is facing the challenge. What I want to know is: What effect does batting in front of the pitcher have on a hitter? 棒球界对於国联球队打线的第八棒—也就是说，在投手前的一棒—有些传统的看法。投手 不太会投出较甜的球给第八棒，因为接下来会对上明显较差的打者。对一位有耐心的第八 棒，这会增加他上垒的机会；对一位球来就打的第八棒，很可能结果是追打坏球。 2008年投手的棒次引起了更多的讨论。这周的红雀酿酒人之战，双方教练都不约而同的把 投手排在第八棒。於是，原本的「第八棒」现在成了打击更好的「第七棒」。 现在我想知道的是，在投手的前一棒打击和其他棒次有什麽不同? How to measure the effect To know how batters handle batting in front of the pitcher, we need to have a point of comparison. In other words, we need a sample of players who have a reasonable number of plate appearances both batting in front of pitchers and batting in front of non-pitchers. Players like that aren't hard to come by. Not only do managers shift players in and out of the 8-hole, but even a batter who starts in that spot every day will regularly hit in front of a pinch-hitter. And, presumably, pitchers use a different strategy with Daryle Ward on deck than they do with Jake Peavy standing there. With that group of batters in hand, we can determine, in the aggregate, how they manage batting both in front of a pitcher and in front of a non-pitcher. The effect turns out to be dramatic. 首先，我们先来蒐集一些在第八棒和其他棒次都打过不少次的打者的资料，比较他们在不 同棒次下的打击情况。 这样的打者倒是不难找到。教练常会换不同的打者打第八棒，即使是万年第八棒的也常常 会上来代打。此外，我们假设投手的投球策略会因为下一棒而有所不同。 从资料看来，「第八棒」对打击的影响还不小。 The algorithm For today, I limited myself to play-by-play data from 2007. Because it's hard to rack up very many at-bats in front of the pitcher, I used a low cut-off: I included a player if he had 20 or more plate appearances with the pitcher on deck. (I'm ignoring tactical shifts, such as the pitcher standing on deck and then being pulled for a pinch-hitter, or vice versa. If a pinch-hitter came in, I'm assuming that everyone knew a pinch-hitter was coming in.) The vast majority of those players had more plate appearances in front of non-pitchers than in front of pitchers. To take just one example, Jack Wilson had more PA batting eighth than elsewhere, but he had only 182 PA with a pitcher on deck against 353 PA with a hitter on deck. To isolate the effect, I used the typical approach employed in measuring Minor League Equivalencies: I equalized the number of PA. So, for Wilson, I reduced his 353 PA in front of non-pitchers to 182. This step keeps any one player from disproportionately affecting one of the two pools ("in front of pitchers" and " in front of non-pitchers"). 资料是以2007年所有超过20个「第八棒」打席的球员统计资料为准。在这里暂时不考虑投 手换代打的可能性。 打多数打者在「第八棒」的机会都不太多。以Jack Wilson而言，他最常打的是「第八棒」 没错，但他在其他棒次的打席总和是「第八棒」打席的两倍。 为了消除这个变因，我把其他棒次的打席缩减到和「第八棒」打席一样多。这样打者在这 两种情况下的统计资料在比例上不会相差太多。 The results Here is how our population compares on a few key statistics: AVG OBP SLG Stk% P/PA In Front of P 0.267 0.330 0.399 61.3% 3.67 In Front of Other 0.230 0.302 0.338 62.8% 3.74 There are quite a few surprises here. I expected that the on-base percentage would be much higher in front of the pitcher. It is, but not for the reason you might expect: Walk rate is actually a little higher without the pitcher batting behind them. Also, the similarity in P/PA suggests that, as a whole, these hitters don't change their approach when batting eighth—or, at least, there is no standard different approach that all hitters take in that spot. The difference in strike percentage is the one comparison that wholeheartedly supports the conventional wisdom. That gap is meaningful, and it confirms that batters see fewer strikes when the pitcher is coming up. The spread might not be as dramatic as some assume, though. With all these resemblances, how do we explain the huge differences in AVG and SLG? These wouldn't be powerful hitters anywhere in the lineup, but they still manage to alter their performance quite a bit. One contrast that may provide a clue is strikeout rate: In front of the pitcher, these players strike out 14.1% of the time, whereas elsewhere, the corresponding number is 17.1%. My guess is that two things are going on. First, pitchers are looking past the No. 8 hitter to the weak batsman on deck, so they are putting themselves in more hitter's counts, thereby cutting down strikeouts and allowing more balls in play. Second, in low-leverage situations with the pitcher on deck, the hurler on the mound is pitching to contact. Like the above, this would also lead to fewer strikeouts and more balls in play. This makes sense: In a situation, say, with the bases empty and two outs, it would be nice to retire the No. 8 hitter and have the pitcher leading off the next inning; it might be easier, though, to give the No. 8 hitter a chance to get himself out on two or three pitches. Either way, there's very little chance of a run scoring. 就和大家想的一样：「第八棒」的打击成绩确实比较好。但，有趣的是，「第八棒」的保 送并不像大家想的那样多。另外，P/PA显示打者的打击策略并没有随棒次而改变。好球率 倒是和传统观念相同；「第八棒」看到的好球比较少。 那麽，是什麽原因造成「第八棒」和其他棒次打击成绩的巨大差异呢？我想，从三振率我 们可以看出一些端倪；「第八棒」：14.1%，其他棒次：17.1% 可能的原因：投手会比较不在意「第八棒」的打击，因为下一棒几乎就是自动出局数，此 外，当「第八棒」上场时通常也都是局面较轻松的时候，这时投手比较会投给打者打。这 样一来「第八棒」能打到的甜球就变多了。 Eight-spot all-stars Fourteen players came to the plate at least 80 times last year with the pitcher on deck. Most of these are names you'll recognize, and it's interesting to see just how much of a boost some of them got with a weak hitter behind them: In Front of Pitcher In Front of Others First Last PA OBP SLG Stk% OBP SLG Stk% Alfredo Amezaga 103 0.359 0.371 61.3% 0.325 0.348 63.1% Brad Ausmus 188 0.332 0.354 60.8% 0.298 0.277 62.9% Craig Counsell 83 0.337 0.274 59.3% 0.308 0.287 60.7% Tony Graffanino 91 0.286 0.277 59.5% 0.293 0.421 60.5% Chris Iannetta 90 0.289 0.375 60.1% 0.346 0.319 60.3% Cesar Izturis 119 0.328 0.360 63.7% 0.290 0.274 64.9% Jason Kendall 89 0.382 0.397 61.9% 0.327 0.353 66.4% David Ross 143 0.282 0.466 59.4% 0.217 0.211 60.8% Carlos Ruiz 198 0.293 0.352 60.0% 0.356 0.409 57.3% Brian Schneider 80 0.300 0.286 57.0% 0.322 0.331 58.8% Chris Snyder 111 0.387 0.536 57.6% 0.323 0.360 58.9% Yorvit Torrealba 115 0.400 0.553 60.6% 0.292 0.290 62.0% Omar Vizquel 139 0.331 0.375 63.6% 0.289 0.285 60.8% Jack Wilson 182 0.357 0.506 62.7% 0.316 0.372 65.0% 有十四位打者打超过80次的「第八棒」，当有投手当垫背时，他们的成绩都明显提升了。 Next steps A better study would use multiple years of data—matched sets of 80-100 PA don't cut it if we want to break down the findings any further. And presumably, breaking down is the direction we want to go. The aggregate numbers, and the handful of players displayed above, agree on the generalities: Batters perform better ahead of the pitcher, and they don't see as many strikes. But the effect is much stronger on some players than others, maybe just because we are working with small samples, but probably, to some extent, because different players handle the role better than others. 现在这个只是最初步的分析，接下来我还会研究年更多年更多「第八棒」打席的资料，这 也是我们未来的目标。 从目前这一大串的数字中，我们可以同意这个说法：「第八棒」的打击确实比较好。当然 ，现在这明显的数字差异也有可能是小样本的误差造成，但是，我想这差异性还是存在， 因为每个「第八棒」都打的特别好。 --

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