In standard baseball lore, hitters are often told to try to spray the ball around the park. Do not hit the ball in just one direction - hit it in all directions. After all, how are fielders supposed to guess where you’re going to go if you hit it to all sides somewhat equally? As a lefty who was constantly out on his front foot early in little league, this approach was drilled into my skull. But is there actually a benefit to spray hitting? Do these players, on average, perform better? Attempting to dissect the common dogma of baseball coaches everywhere, these questions and more will be answered.
Sample
As always in these types of studies, let’s establish the group of players that will be reviewed (the sample). The years examined span from 2006 - 2021, with 2020 data being thrown out of this set. So many unforeseen circumstances from that surprising year make including it a possible error. The start year of 2006 is related to the beginning of Pitch F/X tracking, although pull/opposite spray chart data was available beforehand. The tracking is considered to begin a higher degree of accuracy in that year, although that could be argued as arbitrary. Either way, it provides a great modern picture and a sizeable amount of data to make conclusions about. Within these years, each season was individualized. As the repeatability of being a spray hitter is somewhat unclear to me, I thought it safer to look at each individual season and draw conclusions from a larger set. Only qualified seasons (based on plate appearances) made the cut. This criterion yielded 2,184 total seasons to look over.
Methodology
If you are genuinely not curious about how this study was conducted, feel free to skip to the conclusion. In order to make conclusions about whether being a spray hitter (a hitter that primarily hits to all fields) or a non-spray hitter (a hitter that primarily hits to one or two fields) is beneficial, the actual difference needs to be defined. Unfortunately, there was no mathematical constant established by sabermetricians to state the difference clearly. In the interest of avoiding bias, this article will have multiple levels of being a spray hitter, defined by the minimum percent of balls in play to every side. Each level will split the players into two groups - those that are above and below the threshold.
From these groups, major batting statistics such as wRC+, wOBA, OPS, and BABIP (Batting Average on Balls In Play) will be included. WRC+, wOBA, and OPS are offensive production metrics, and BABIP is used because while spray hitters are supposed to be better in general according to conventional theory, they are also supposed to be better at hitting baseballs past fielders. As fielders could not guess where said ball would go, the hitters' BABIP should be higher (again, in theory).
While comparing the two groups will show which one is better than the other, these differences are nominal. Without context, these nominal differences could mean lots of things. In the interest of precision, a baseline for the samples needs to be provided so that the differences can be compared for their actual meaning. Below are the averages for the whole sample of the five statistics aforementioned:
The baseline is clear for what the average level of production is. Now, how do these two types of hitters actually compare? As mentioned earlier, there will be multiple thresholds that rely on the minimum number of balls in play to each side of the field to separate these groups. For example, in this study, Player A pulled 40%, hit to center 37%, and went opposite field on 23% of all balls hit in play. If the threshold in the study were a minimum of 27.5% to each side of the field, he would not meet the required mark, designating him as a non-spray hitter. But if Player B pulled 30%, hit to center 32%, and went opposite field on 38% of hits, he would be classified as a spray hitter. Now having a clear example, the findings should be more easily understandable.
Preliminary Findings
The results seemed to illustrate a few trends. For starters, the non-spray hitters under all thresholds performed reasonably better. These hitters produced more value in terms of wRC+, wOBA, and OPS, beating the average sample every time. On the contrary, the spray hitters produced worse than the average. Under every threshold, the aforementioned hitting statistics were not as good as the average of the entire sample. As each criterion was upgraded to allow for a stricter definition of a spray-hitter, the spray-hitting group produced less and less.
While the players that hit to all fields appear to have added less run value to their teams, they did succeed in one aspect - BABIP. Batting Average on Balls In Play is conventionally viewed as a complete luck statistic - nothing could be farther from the truth. Sprint Speeds and Hard Hit rates are known to play crucial parts in a player's overall BABIP, with better metrics in both categories correlating to a higher rate of success. This is due to the fact that fielders have a tougher time throwing out faster players and fielding harder-hit baseballs. But from these findings, BABIP could possibly be influenced by the ability to spray baseballs around the field. Every spray threshold did 19-20 BABIP points better than its non-spray counterpart and exceeded the sample average of .307 by a wide margin. The conventional theory states that BABIP improves for spray hitters due to a fielder’s increased difficulty of being able to expect where the ball is going - these numbers seem to confirm that wisdom.
Further Evidence
These preliminary findings suggest that spray-hitters tend to produce less and have a higher batting average on balls in play in comparison to non-spray hitters. But is the spray-hitting to blame for such factors, or is this simply a convenient correlation? Let’s aim for certainty. While establishing thresholds and noticing different aspects is one way to spot a potential relationship, it does not put the question to rest. For a more firm answer, instead of groups, the level of spray-hitting is to be put on a scale. The perfect way to do this is through standard deviation, which measures how spread out data points are. For this instance, if a player is not a spray-hitter and has big differences between his percentages of balls hit to each field, that player's standard deviation will be high. If a player is a spray hitter with small differences between his percentages of balls hit to each field, his standard deviation will be low. These standard deviations, as well as the offensive metrics, are then able to be regressed through the r-squared measure, which estimates the amount of causation for a given factor influencing a set of numbers. It is computed on a scale of 0 to 1, with 1 equating to full causation and 0 equating to no causation. This leads to estimates about the impact of spray-hitting on different offensive metrics, providing needed definitive answers. Pictured below are the scores for each metric:
Beginning with the main offensive statistics of OPS, wOBA, and wRC+, it becomes apparent that correlation does not mean causation. From the preliminary look, increased spray-hitting ability looked to be related to decreased performance. That is not reality. The R-squared for each statistic hovered around the 0.01 to 0.02 mark, which means that almost no causation was evident. The trend observed was likely due to variable chance - spray hitting has nothing to do with increased offensive value, disproving the traditional theory of utilizing spray hitting to increase value.
Compared to the other categories, however, BABIP is a completely different story. The R-squared for the statistic is 0.1651, meaning that 16.5% of a player's BABIP can be owed to a hitter’s spray factor. That might not be an extremely large number, but it is somewhat significant. BABIP can already be owed to hard hit rates and speed. Now, it is proven that hitting to all sides of the field also affects it. This shows that the conventional knowledge is right - hitting to all fields is a factor in making it more difficult for fielders to make an out.
A befuddling question emerged from these confirmed points - why did players with increased BABIP generally not perform better? A hitter's ability to increase his BABIP should add value. The more hits a player has, the higher their wOBA should be. On average, these spray hitters' wOBAs weren't significantly bigger or smaller than their counterparts, suggesting that these types of players do not produce value by hitting for power. ISO (Isolated Power) is a great way of identifying this power trait. While not included in the chart, a player's standard deviation and ISO have a positive correlation, meaning that the players in the sample that hit one or two sides tend to hit for more power. A .1484 R-Squared value confirms that spray hitting can be partially to blame for lost power. There is a chance that these hitters tend to not have much power in the first place, hence their spray-hitting approach. But at that point, this becomes a "what came first: the chicken or the egg?" situation. Does spray hitting cause a loss of power, or do spray hitters not have the power to begin with? A definite answer is not obvious, but a mixture of both of those explanations seems possible.
Conclusion
The above findings are littered with statistical jargon that can make the findings somewhat complicated - let's simplify. Common baseball traditionalists have forever argued that being able to hit to all fields provides a benefit to players - this notion held up to an extent. It is not fully true, although it is far from being entirely false - there is more gray area in the answer than originally intended.
Offensive Impact of Being A Spray Hitter
Based on the results of the data, hitters that hit to all fields perform no better than those that mainly hit to one or two fields. In fact, spray-hitting has almost no effect whatsoever on overall offensive outcomes. Coaches, especially in Major League Baseball, that insist that being able to hit everywhere is a necessity are sorely mistaken. Great hitters can hit balls in lots of different directions - trying to adjust an approach to "aim" the ball will more than likely serve to the player's detriment. Let hitters go in whatever directions they feel most comfortable with.
Avoiding Fielded Plays
On average, offensive batsmen that hit to all fields do better in BABIP than their counterparts. BABIP is known to be influenced by speed, hard hit percentages, and barrel rates, but being able to spray across fields is also a factor. Spray hitting has a positive effect on a player's BABIP. If a player's goal is to add a few extra hits here or there, he will benefit from hitting to all fields. Conventional fans and coaches are right - it does help hitters avoid more fielded balls that result in outs. However, added overall offensive value is still negligible, as mentioned above. This is primarily due to the fact that these types of hitters have worse power numbers on average, which can limit their production value.
As stated, this answer can't just be summed up in black and white. The way that players hit affects the game in all sorts of ways. Some were mentioned here, while others float in baseball theory. Spray hitting has been generally looked at as an important tool, though that emphasis should probably end. The current emphasis does not equate to its actual impact, making people focus on the wrong things. Instead of worrying about a ball's direction, worry about its launch angle and exit velocity - these are much more important in adding value to a team.
"Ichiro Suzuki" via Erik Drost licensed under CC BY 2.0
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