Single-game plus-minus is often close to useless, which is why analytics folks have attempted to come up with better plus-minus indicators, such as ESPN’s Real Plus-Minus (RPM). Real plus-minus attempts to tease apart the value of each player’s defensive plus-minus and offensive plus-minus in order to better measure the two-way effectiveness of each player. I just learned that Khris Middleton, of Milwaukee, is the 8th-most effective defensive player in the NBA this year, according to Real Plus-Minus. I appreciate the fact that defensive impact is being measured in ways that it never was before. Milwaukee’s defense has been far better than anyone could have predicted this year, and they’re doing it all without Larry Sanders, which is amazing. Everyone knows about Giannis’ defense. But not many know about Middleton.
Still, I want to bring attention back to the single box score and the fact that plus-minus should not have it’s own column in that sacred space. (It’s hilarious to see, but the modern newspaper, at least the San Francisco Chronicle, box scores still keep three-pointers below the chart-area of the box score. Old habits…)
One more drop in the overflowing river of plus-minus misleading river: Derrick Williams of Sacramento recently pulled off a miraculous feat, which adds one more piece of evidence that focusing on single-game plus/minus stats is often misleading.
Williams’ line: 23 minutes, shooting 1 of 5 from the field, collecting 3 points, 1 rebound, 1 assist, and 1 steal, and 1 turnover. His plus/minus for the game: +20.
Williams benefited from Ben McLemore’s early 4th quarter spark and from happening to match-up against a very weak and rusty Charlotte bench that included the ghost of Jason Maxiell, the mystery man Lance Stephenson, and a first-game back Kemba Walker (2 of 9).
While Williams ended with a plus-20, Gerald Henderson of Charlotte finished with a minus-14 in his 34 minutes of game action. Henderson finished with 17 points (7 of 16), 11 assists and 6 rebounds, and a single turnover. Of course, Henderson was surrounded by offensively inept players and an extremely rusty Walker.
There are too many factors in a single game to give us one number that tells a real story. Take the plus-minus stat and toss it in the garbage. Real plus-minus does a better job, but it’s still too simplistic to rely on.