TAMPA, Fla. — James Paxton is a starting pitcher for the Yankees, not a statistics innovator. But during the 2018 season with the Seattle Mariners, before his off-season trade to New York, he found a novel way to measure his efficiency and aggressiveness on the mound.
Paxton, 30, asked the Mariners’ analytics department to give him a printout of a statistic he was tracking himself: the percentage of at-bats that, after three pitches, were either in a 1-2 count or already completed. He named the statistic A3P— After 3 Pitches — and monitors it often, rather than relying on more conventional statistics such as earned run average or wins and losses.
“I can’t control some of those things,” he said. “I try to focus on the things I can control. And I can control if I’m attacking the hitter.”
Baseball is saturated with statistics. Want to know which hitters do the best against low fastballs over 95 miles per hour from left-handed relief pitchers? Want to know which outfielders cover the most ground or what percent of the time a similar play resulted in an out? Those can be found in a matter of clicks online.
As the ways to quantify what happens on the field continually evolve, so has the debate over which measurements are best. In modern baseball circles, many traditional statistics no longer hold the same power.
“I don’t think batting averages are a thing now,” said Luke Voit, 28, a Yankees first baseman.
In the Yankees’ clubhouse, there is a wide range of ways in which players evaluate themselves through statistics, some relying on the conventional measures with others leaning toward the contemporary. A casual poll of players provided a window into their thinking and which skills they value — or don’t.
“I don’t look at anything,” said C. C. Sabathia, 38, who is entering the 19th and final season of a distinguished career that includes a Cy Young Award and six All-Star selections.
“I don’t understand WHIP,” he added about an oft-used statistic that adds walks and hits before dividing that total by innings pitched. “All I know is E.R.A., wins and losses. I’m old school in that sense.”
Luis Severino, 25, the Yankees’ injured ace, may have grown up in a different era of baseball, but he feels the same way. His go-to statistics for self-evaluation are E.R.A. and innings pitched, two categories in which he has led the Yankees’ rotation the past two seasons.
His fellow starter J. A. Happ, 36, said he follows win-loss records and E.R.A. because they are ubiquitous. But over the years, he has found himself gravitating toward WHIP after a conversation with R. A. Dickey, a former Cy Young Award winner, when they were both Toronto Blue Jays.
“It started to make sense that generally speaking — although numbers can prove anything — that, if you’re doing a good job of keeping the walks and hits down, then you’re doing pretty good over all,” Happ said.
During a recent spring training meeting, Yankees coaches stressed the need to be aggressive. Paxton takes this to heart: He is among the best in baseball at throwing strikes. In addition to his A3P statistic, Paxton checks on the percentage of first pitches in each plate appearance that were strikes. His goal is to reach at least 70 percent; he was at 66 percent last season, according to Baseball-Reference.com.
“By thinking about this often, and if I can do it consistently, I’m putting myself in a good spot to have success,” he said.
As for offensive statistics, outfielder Aaron Judge, the Yankees’ best all-around hitter, regularly checks two statistics during the season to see if he is doing his job as one of the team’s main sluggers: runs and R.B.I. And he will examine how well he did with runners on base or in scoring position.
Aaron Judge is one of the largest players in baseball, but he prides himself on the ability to aggressively run the bases.CreditBen Solomon for The New York Times
“That’s the name of the game: scoring more runs than the other team,” he said.
But the R.B.I. statistic has been de-emphasized by modern baseball because it is as much a product of a team’s lineup as the individual hitter’s skill. Put Judge, 26, in the worst lineup in baseball last season and he would have a harder time cracking the cherished 100-R.B.I. plateau.
“It still shows value to me,” Judge said. “For me, I always look at the guys that are leading in R.B.I. on their team, and usually those teams are doing better.”
Another measure Judge cited seemed counterintuitive. At 6 foot 7, Judge is one of the tallest position players in baseball history. But he prides himself on being faster than you would think; 374 players were slower than him last season, according to Major League Baseball’s Statcast data. Judge keeps tabs on how often he is scoring from second base on a single or advancing from first to third as a base runner.
“If you look all over the game, you’ll see a lot of guys just go first to second,” he said. “There’s a lot more chances to go first to third than people think. You just got to be aggressive.”
Judge’s fellow slugger, Giancarlo Stanton, prefers to examine which of his hitting tendencies opposing pitchers might exploit. When scrutinizing his performance with runners in scoring position, he said, he examines his mental approach rather than a popular statistic like on-base-plus-slugging percentage (O.P.S.).
Stanton, 29, does check his chase rate, a phrase for the percentage of times a batter swings at pitches outside the strike zone. During Stanton’s first season with the Yankees in 2018 after a trade from the Miami Marlins, his chase rate jumped more than five percentage points to nearly 33 percent from the previous season, according to FanGraphs.com. That may have contributed to his decline in overall power production.
Several players said they did not focus on any preferred statistics.
“If you look only at R.B.I., then maybe you don’t hit much in terms of average — or the reverse,” said catcher Gary Sanchez, 26, who is hoping to bounce back from the worst all-around season of his career and return to his 2017 All-Star form. “It’s all important. You try to do it all.”
Others said they avoided statistics entirely. Relief pitcher Dellin Betances, 30, said he knew exactly how he was performing without the numbers to break it down. Troy Tulowitzki, 34, the Yankees’ primary shortstop while Didi Gregorius recovers from elbow surgery, cited an unheard-of statistic: “I look at a winning player.”
Tulowitzki pointed to the Yankees’ new infielder D. J. LeMahieu, 30, a former teammate from their days with the Colorado Rockies, as one. LeMahieu, a career .298 hitter who once won a batting title, loosely keeps tabs on the quality of his at-bats and his strikeouts.
Some players, like relief pitchers Chad Green, 27, and Adam Ottavino, 33, have adapted well to the data revolution in baseball.
Even closer Yankees closer Aroldis Chapman, 31, an advanced statistics neophyte, said he has learned since his half season with the Chicago Cubs in 2016 that one applies well to him: his outings usually turn out better when he gets the first batter out. He has tracked it himself since.
Ottavino, though, is on his own level. During the season, he checks two statistics he believes reflect how he is throwing: first-strike and walk percentages. At the end of the season, he dives deeply into how he threw the ball, using advanced statistics like xwOBA (expected weight on-base average), which in layman’s terms, essentially measures the quality of the contact made against him.
He labeled other statistics, like E.R.A. or the scoring percentage of inherited base runners, as faulty.
“We’re trying to strip away all the luck factors so you can be as real with yourself as possible,” he said. “If you’re not doing that, you’re going to ride the roller coaster really bad, and you’re lying to yourself.”
Even if some of Ottavino’s teammates are not quite there yet in terms of the game’s advanced numbers, the Yankees’ robust analytics department is there to help them all break down the multitude of statistics in the game. The players just have to ask.