Lee Mendelowitz is a lifelong Major League Baseball fan, but he still had to be talked into working for one of its teams.

He was pursuing his Ph.D. in applied mathematics at the University of Maryland in 2014, researching software algorithms that work with a particular type of genomic mapping data, when a Washington Nationals official announced at a data science networking event an internship opportunity that might fit the attendees’ skillsets. 

Mendelowitz applied and the Nationals offered him the internship, but making a decision wasn’t an easy call.

“I was concerned about whether it would be a good decision for my professional development,” he said. “Here I am trying to wrap up my Ph.D., and I take two-and-a-half or three months off to work in baseball? Is that going to set me back in my Ph.D. work?” 

It turned out to be an “incredible” experience, and Mendelowitz M.S. ’12, Ph.D. ’15 stayed on with the team and today is its director of baseball research. With tonight’s Opening Day game at Nationals Park, he’ll again be crunching the numbers—speed and trajectory of a pitch, the positioning of players on the field or even the parameters of a particular umpire’s strike zone—to help Washington win. 

“I used to just watch the game. Now it feels like I’m watching the game within the game,” he said. “There are just so many more details to pay attention to.”

Mendelowitz grew up in Bergen County, New Jersey, rooting for the Yankees and going to games with his dad and his brothers.  At school, mathematics and science came easily to him, and in 2004 he went on to Cornell University, where he earned his undergraduate degree in applied physics. He then accepted an entry-level systems engineering position at Raytheon Technologies in Massachusetts. 

But he couldn’t stop thinking about an applied math course that captured his interest at Cornell. “It was all about mathematical modeling with differential equations and complex behaviors that can arise from simple sets of equations,” he said. “I felt a calling—I wanted to go back to school and pursue applied math.”

Mendelowitz and his then-girlfriend, now wife, Diana Cohn, coordinated their search for graduate schools. While she looked at law schools in the D.C. area, he looked into the applied mathematics & statistics, and scientific computation (AMSC) program at UMD.

It was during his time at UMD, in 2013, that he launched an ambitious side project: tracking escalator breakdowns in the D.C. Metro system. 

“The initial idea I had was to build this Twitter bot that would tweet every time that an escalator stopped working in the D.C. Metrorail system,” Mendelowitz said. “I was living in D.C., so I was taking Metro to commute every day back and forth to College Park. When you’re commuting, it’s especially annoying when escalators don’t work and you have to walk up three stories. So, I thought this would be fun, and no one else had done anything like it.”

Due to popular demand, particularly from people with disabilities trying to navigate Metro, he added elevator outages and other information, posting it all on a website, dcmetrometrics.com. He kept it up and running for several years until he no longer had the time or energy to maintain it—baseball and life were keeping him busy. 

Interning for the Nationals, he worked on a number of projects, including one where he modeled the strike zone of each umpire, then he stayed on with the team as a consultant. After completing his Ph.D., he went to work for the team full time as an analyst. By this time, the Nationals and other major league teams had more data to work with than ever before thanks to StatCast, MLB’s player tracking system.

“We know how hard the ball was hit, and in what direction, we know how far the ball travelled, we know how quickly the center fielder reacted and the route he took to try to make the play, Mendelowitz said. “The ultimate goal is to use this kind of information to make decisions that translate to wins on the field.”

Now, after more than five years with the Nationals—including the thrill of being part of the team’s World Series win in 2019—he is hard pressed to think of a job that would be a better fit.

“I was lucky to get the internship, lucky to get a full-time offer and the Nationals deciding there’s a role for people like me to work in baseball,” he said. “I feel very fortunate and grateful, that’s for sure.”