Why you should care
Who doesn’t want to stay 21 forever?
The McDonald’s Big Mac and Spurs Big Man Tim Duncan have a good deal in common. Just as you always know what you’re getting with a Golden Arches order (well, kind of), fans could expect the same savory consistency from the power forward whom Charles Barkley once dubbed Groundhog Day. Based on Duncan’s PER (player efficiency rating) 36-minutes stats, which measure a player’s per-minute, rather than game, production:
His output has remained nearly constant over his entire career.
Duncan recently announced his retirement after 19 years in the NBA, all played with the same San Antonio team. Duncan, now 40, has been revered as one of the most efficient players of his generation; his minute-by-minute reliability, however, hasn’t netted quite as much recognition (except among Redditors and advanced data miners). His first season — the same year Boogie Nights hit theaters — the five-time NBA champion posted a 108 offensive rating and 95 defensive rating. Last season, his final, those stats were 107 and 96. That stability, though insufferable to watch, is the defining mark of the Big Fundamental’s career.
The PER 36 stat calculates field goals, free throws, three-pointers, assists, rebounds, blocks and steals, as well as missed shots, turnovers and personal fouls, on a minute-by-minute basis. Some, including its inventor, stat analyst John Hollinger, argue that PERs better capture effectiveness, since they value quality of play over minutes played. “It’s a good way to measure performance from players like Tim Duncan, whose minutes started to trail off the second half of his career,” says MIT’s Joel Brooks, who studies how we can use machine learning to better understand sports. But others point out that as minutes and roles increase, production and efficiency often decrease, so it’s not fair to compare players off the bench with starters.
Dan Altman, founder of North Yard Analytics, says, “He’s exactly the type of player we’d expect to have consistent numbers.” Duncan’s played his entire career at the same position, on the same team and with the same coach — without serious injury. “As he aged, his deepening experience in the game may have compensated for any erosion of his physical abilities,” Altman adds.
But he also points out that, for a player’s per-minute numbers to stay steady, his team has to spend relatively the same amount of time on offense and defense season after season. So unless the Spurs showed the same consistency, Duncan’s numbers are likely at least partly coincidental. In that case, the 6′11″, 250-pound veteran still has his legacy as a top scorer, rebounder and shot blocker. “There’s a lot to his game the box scores and PERs don’t capture,” Brooks says. Like his Eeyore expression and unnerving composure.