News flash: being an umpire is hard. Their job is to judge whether a ball that’s capable of moving upwards of 100 MPH or breaking 25+ inches crossed through an imaginary zone before being caught. I don’t think many would argue that they have it easy, but every baseball fan would be lying if they claimed they’ve never been upset at a call, whether it’s your cleanup hitter getting rung up to end a rally or the opposing team’s leadoff hitter eking out a full-count walk on a pitch just inside. These calls have been in the game since its inception and will stay a part of the game while umpires still call balls and strikes. Finally being able to watch MLB games again got Tyler Zombro and I thinking about the trends in these calls and if umpires have an inherent bias to expand the strike zone for certain locations.

新闻快讯：成为裁判员很难。 他们的工作是判断一个能够向上移动100英里/小时或突破25英寸以上的球是否在被抓住之前越过了一个假想区域。 我认为很多人都不会认为这样做很简单，但是如果每个棒球迷都声称自己从未在通话中感到沮丧，那么不管他们是清理清除手准备结束一场集会还是对方球队的比赛，他们都会撒谎开场击球员芯吸出来只是在内部间距的全算的步行路程。 自游戏问世以来，这些调用就一直存在于游戏中，并且当裁判仍在召唤球和罢工时，它们仍将保留在游戏中。 终于能够再次观看MLB比赛了， Tyler Zombro和我考虑了这些电话的趋势以及裁判员是否固有地偏向于扩大某些地区的罢工区。

方法 (Methodology)

The data set used was filtered down to only include pitches that were called strikes or balls as there’s no way of knowing what a pitch would have been called otherwise. A universal strike zone was then constructed using the PitchGrader model to help mitigate the height difference between batters. This provides a clear top (44.08" or 3.67' off the ground) and bottom (18.29" or 1.52' off the ground) to the zone while also giving a little leeway (1.47") off the edges of the plate since any part of the ball has to cross the strike zone to be a strike. The pitches were then filtered to be reasonably close to the strike zone to constrain wild misses.

所使用的数据集被过滤掉，只包括被称为打击或球的音高，因为无法知道否则将被称为什么音高。 然后使用PitchGrader模型构建通用打击区，以帮助减轻击球手之间的高度差。 这样可以为该区域提供一个清晰的顶部(离地面44.08英寸或3.67')和底部(离地面18.29英寸或1.52')，同时由于板子的任何部分都留有一点余地(1.47“)。球必须越过击球区才算是击球，然后对球距进行过滤，使其合理地接近击球区，以限制野外射门。

结果 (Results)

左手击球手 (Left-Handed Hitters)

Looking at a two-inch range off the plate against left-handed hitters shows that the outside pitches are called strikes at a 48% clip compared to a 21% clip inside. Increasing the range to five inches shows the same result: pitches off the plate away are called strikes much more often (26% away contrasted with 10% in). This disparity between outside and inside pitches shrinks when looking strictly at pitches from left-handed pitchers, giving credence to the idea that opposite-handed pitchers can live off the plate away much better.

从左手击球手处两英寸的范围内可以看出，外侧投球被称为击球，击球率为48％，而内侧为21％。 将射程增加到5英寸可显示出相同的结果：离开击球板的步伐被称为击球的频率更高(相距26％，相距10％)。 当严格看左手投手的投球时，外部和内部投球之间的差异缩小了，这证明了相反的投手可以更好地生活在盘上的想法。

右撇子 (Right-Handed Hitters)

For right-handed batters, umpires are much more apt to expand the strike zone off the plate. Within the 2-inch window, 50% of outside pitches are called strikes while only 32% of those inside pitches are called strikes. Left-handed pitchers enjoy more success away within that zone with 54% of their pitches off the plate away being called strikes, backing up the idea that opposite-handed pitchers can live away better. In the 5-inch range, outside pitches are called strikes 28% of the time compared to 17% for inside pitches.

对于惯用右手的击球手而言，裁判更容易将击球区扩大到板外。 在2英寸窗口内，外部音高的50％被称为打击，而内部音高的仅32％被称为打击。 左撇子投手在该区域内获得了更大的成功，他们的投篮命中率有54％被称为打击，这证明了左撇子投手可以更好地生活。 在5英寸范围内，外部音高在28％的时间内被称为敲击，而内部音高则为17％。

总体 (Overall)

Umpires have a clear bias towards expanding the zone for outside pitches. While looking at pitches an inch outside/inside our zone, 58% of those outside pitches were called strikes compared to 36% of those inside. While both percentages are high for pitches that should probably be classified as balls, outside pitches were over 1.5 times more likely to be called strikes compared to inside pitches within the same range.

裁判员显然倾向于扩大外部球场的区域。 在查看我们区域外/内一英寸的间距时，其中58％的外部间距称为罢工，而内部的36％被称为罢工。 尽管对于应该归类为球的球场来说，这两个百分比都很高，但与相同范围内的球场相比，外侧的球场被称为打击的可能性高1.5倍。

The difference in rate becomes even more pronounced the further off the plate you look. A range of two inches off the plate shows that outside pitches are 1.81 times more likely to be called strikes while increasing the range to 5 inches shows that outside pitches are almost twice as likely to be called strikes. The visual below showcases how much further off pitches away are called compared to those inside. It’s clear that umpires have called more strikes away and do so at a much higher rate.

速率差异越显着，离您的盘子越远。 距离板两英寸的范围表示外部音高被称为打击的可能性高1.81倍，而将范围增大到5英寸则表明外部音高被称为打击的可能性几乎是两倍。 下面的视觉效果展示了与内部距离相比，远处的距离被调用的距离。 显然，裁判员要求更多的罢工，而且罢工率更高。

I believe the main cause of this outside bias is that umpires set up between the catcher and batter, providing them a much better picture of the inside part of the plate. I believe this is also heightened with matchups of the same handedness as pitches on the inside part of the plate will approach from a straighter angle and therefore easier to judge its location.

我相信造成这种外部偏差的主要原因是在接球手和击球手之间建立了裁判员，从而使他们对盘子的内部有了更好的了解。 我相信，如果用相同的惯性进行比赛，这也会增加，因为板内侧的螺距会从更直的角度接近，因此更容易判断其位置。

With how much pitches move in today’s game, it’s not a surprise that more and more pitches are being called off of the plate. Pitchers can use this to their advantage and work away more often when they need to steal a strike. Getting two or three extra calls a game can be the difference between getting pulled early or putting together a quality start.

在当今比赛中，随着音高的变化，越来越多的音调被取消就不足为奇了。 投手可以利用这一点来发挥自己的优势，并且在需要偷罢工时可以更频繁地工作。 在游戏中多打两个或三个电话，可能是提早获得比赛或开始高质量比赛的区别。

Further research is necessary to understand how and when the zone is expanded. Is it mainly in two-strike counts? Do fastballs or breaking balls get called strikes off the plate more? These questions and more will help us better understand what’s going on in the mind of an umpire… at least until the robots take over.

有必要进行进一步的研究以了解区域扩展的方式和时间。 主要是两次打击吗？ 快球或断球被称为击球更多吗？ 这些问题以及更多的问题将帮助我们更好地理解裁判员的想法……至少在机器人接管之前。

Thank you for reading. You can find more insights from Tyler and I at rdbaseballacademy.com. Please feel free to reach out to me on Twitter @k_camden for any further discussion or feedback.

感谢您的阅读。 在rdbaseballacademy.com上可以找到Tyler和我的更多见解。 请随时通过Twitter @k_camden与我联系， 以获取进一步的讨论或反馈。