Inconsistent Manufacturing Suspected Cause of Homer-Happy MLB Season
Without a doubt, the 2017 Major League Baseball season has been one for the record books. Currently, the leagues is poised to shatter the average home runs per game average of 1.17 by almost a tenth of a point (MLB average stands at 1.26 home runs per game at the moment). What this means is that if the league continues this pace, they will effectively destroy the previous single season home run record from 2000 by an impressively mystifying 350 additional homers (roughly 6400 homeruns). And although layman's logic would point towards advances in science or athlete training as the culprit, what many researchers are now finding is almost equally amazing: the baseballs themselves are at least partially responsible for the increase and it's due to inconsistent manufacturing.
The baseball wasn't initially expected as the source behind the recent spate of homers in the Major League. Last year, Ben Lindbergh and Rob Arthur began looking at the data to understand the sudden spike in home runs around the league. Beginning in the '09 season, the average runs per game inning to decline, from 4.7 runs per inning in '08 and eventually falling to 3.9 by the end of 2014. Something strange was happening in 2014, however. At the end of the season and into the postseason, teams that were still alive saw their runs spike from 4.06 at the beginning of the season to an average of 4.25 by the end of the season. Then in 2015, things got more interesting.
Initially, 2010 was thought to be the "Year of the Pitcher", with many observers and commentators praising the explosion of talent at the mound for producing runs at a much lower rate than they had in any full season prior to 2010. So when the 2010 season kicked off and we witnessed an explosion of home runs that couldn't be attributed to anything like an increased strike zone or increased percentage of contact (at-bats minus strikeouts). What turned out to be the actual cause would take insiders and observers almost four more years to understand.
The culprit, as it turns out, was the ball itself. In June, Mitchel Lichtman and Ben Lindbergh started studying the official game ball in an attempt to understand what may be contributing to the spike in homers. Through experimentation on more than three dozen baseballs, they found what they had begun to suspect: the baseballs from 2015 were "bouncier" than previously. As they continued to look at historically used game balls and evaluate newer game balls, they noticed that the physical makeup of the ball had seemingly changed. The new balls were now smoother and the seams smaller, subjecting the ball to less air resistance. Additionally, the team found that the balls had begun to become "harder" providing for a better energy return when struck with a bat. The "problem" was that there was no announcement of changes being made to the official ball.
The MLB for their part have denied that any such changes were made to the official game ball and that all materials currently in use are identical to previous generations. They also note that all game balls must fall within the league standard, which may have been left purposely wide so as to retain some unpredictability to the game. Anecdotally, players and coaches also seem to believe that a change has been made to the ball. In a recent interview with the Orange County Register, New York Mets manager Terry Collins said "The seams of the ball are definitely lower...and there is no question that the ball is harder." His voice joins that of Jake Arrieta ("I'll get a ball hit back that is oblong shaped and that never happened until this year"), Andrew McCutchen and pitcher Justin Verlander who have all mentioned changes to the official ball in recent months.
So what does this have to do with inventory solutions? Well in a nutshell, this is a pretty low-stakes example of the importance of consistency in your products. Small changes can have large impacts and in other cases could open your business up to unwelcome or unexpected attention. Having solid, reliable, and well-documented bills of material and assembly instructions could mean a world of difference and might help as a source of information if you are just now beginning to establish standardization across your products.
What the moneyball data seems to suggest now is that after years of fluctuation, the performance of game balls is beginning to become consistent. By evaluating the standard of deviation in drag over the last few years, the trend is that the balls used across the league have become much more homogenous in their performance. One could suppose that with the league disavowing any knowledge of changes to the ball or the standards by which they are evaluated, the entire incident could be chalked up to a decade-long trend to bring standardization to baseball with an acceleration within the past two years pointing towards a game ball that would perform predictably game after game.
And for those that are curious, here's a video from How It's Made detailing the process: