BYU CS Student's Research Helps Texas Rangers Win 2023 World Series
June 27, 2024
“It was still stressful, but it was also an amazing experience to be with the whole organization and to all be working together toward the common goal. And amazing to watch some of the best players in the world making plays all over the field.”
BYU Student Awarded 2023 World Series Ring
Will Melville, a PhD student in the BYU Computer Science Department who works with Dr. Grimsman and Dr. Archibald, presented a paper at the MIT Sloan Sports Analytics conference in Boston and was runner-up in the Research paper competition.
Melville, who works as an analyst with the Texas Rangers, started this project because of the Rangers desire to strengthen their defense. The Rangers won the World Series in November 2023 using a version of Melville’s model to position their outfielders, and this year they are using the model to position the infielders as well. Melville was presented a World Series Ring for his contribution.
The paper is titled "Optimizing Baseball Fielder Positioning with Consideration for Adaptable Hitters."
Abstract: This paper presents a novel approach to positioning baseball fielders to maximize expected outs or minimize expected runs allowed against an opposing hitter. We find evidence that our positioning approach is an improvement over MLB average positioning in terms of both hits and runs allowed. We then extend our approach to adaptable hitters who adjust their batted ball strategy in response to the defense’s positioning strategy by modeling the interaction as a zero-sum game and solving for an equilibrium pair of strategies. We demonstrate two examples where the game theory model is appropriate: against shift-beating hitters who pull the ball less frequently when the defense shifts against them and against pull-heavy left-handed hitters who threaten to bunt against an extreme shift.
Melville explains that the goal of this paper was to come up with a method to position baseball fielders against hitters. Shifting is a strategy in baseball that became popular in around 2015, where in a line of defense, if a hitter has a strong tendency to one side of the field or the other, the defense loads that side up with extra fielders. They wanted to come up with their own method to position fielders. Their idea is if they identify a hitter who is observing the shifting strategy and then hitting their ball on the now empty side of the field, to combat this they settle for a Nash equilibrium positioning strategy, which is a strategy where both the defense and the batter have no incentive to deviate strategy, so if the defensive moved position they would be worse off, they would give up more hits. If the batter started hitting the ball differently, they would also be worse off.
Melville explains that coming up with a new positioning strategy is not very new research, but what made their research so novel is their "game theoretical" idea of what to do with a hitter who was changing their strategy to combat shifting. For more information check out the video below!