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ANALYSIS: What do Nets have for the stretch run? ProfessorB gives us his take

In his day job, ProfessorB is an award-winning social scientist. His writing has appeared in the New York Times, Washington Post, and other major media outlets. But he also dabbles in NetsWorld and this is his first of what we hope will be many contributions to ND.

NBA: Brooklyn Nets at Boston Celtics Paul Rutherford-USA TODAY Sports

Seventeen games to go before the playoffs (or play-ins?). With James Harden gone and Kyrie Irving still mostly unavailable, the Nets are, more than ever, Kevin Durant’s team. Fortunately, KD is back in the lineup. But what lineup is that? Injuries and absences have forced Steve Nash to employ dozens of different lineups over the course of the season, relying on journeymen and rookies to play big minutes in unaccustomed roles. As the Nets gear up for the stretch run, here’s a look at who has come through and who has disappointed.

Real Plus-Minus

ESPN recently began posting real plus-minus ratings for the 2021-22 season. Unlike most basketball statistics, these ratings attempt to capture the totality of each player’s contributions to his team’s success or failure. And unlike most other statistics, they do so by focusing on what really matters—how many points were scored or allowed on each possession. The ratings help explain why the Nets are where they are, and perhaps how they might pull things together for the playoff push.

Casual fans see players’ most obvious contributions, like points per game and rebounds per game. But basketball is a complex, fast-moving team game, and a lot hinges on such hard-to-measure factors as help defense, hockey assists, screens, and box-outs. Raw plus-minus numbers shed some light on those contributions by measuring how well the team does, overall, when a given player is on the court. That’s a start. But there are nine other guys on the court at any given time. What about their contributions?

Real plus-minus ratings attempt to take them into account, disentangling the distinct contributions of each player on each possession. Obviously, doing that requires some assumptions—most importantly, that the offensive and defensive contributions of each player are constant and independent of who else is on the court. That is a simplification, but not a wildly unreasonable one. In effect, the ratings average over all the circumstances in which each player has played, boiling his performance on each side of the ball down to a single number.

If a player’s team runs an offense that doesn’t suit him, or plays him out of position, the rating will not reflect his true ability; but it will reflect his contribution given those circumstances. If two players are especially good playing together, both their ratings will be higher, but only to the extent that they actually do play together. On the other hand, if a player “makes everyone around him better” than they are playing with others, the rating system will rightly credit him for that success.

If two players are on or off the court together on every possession, it is naturally impossible to distinguish their contributions without bringing additional data or assumptions to bear. Even in less extreme cases, the metric will struggle to distinguish the contributions of players who rarely play apart, or simply rarely play. In those cases, especially, it is worth bearing in mind that the ratings are statistical estimates with a good deal of imprecision. As the season goes on and minutes accumulate, the ratings (which are updated daily) will gradually provide a more accurate reflection of each player’s contribution.

The ratings are denominated in net points per 100 possessions on each side of the ball, with zero representing a league-average performance. The overall distribution is skewed by the productivity of stars, so most players end up with negative ratings. (The 225th-best player in the league, 7th or 8th best on an average team, has a -1.5 rating.)

Some fans have violent negative reactions to statistical evidence that contradicts their own “eye tests.” Since the ratings are inevitably imprecise, especially for players who haven’t played much, you should feel free to discount or dismiss as “statistical flukes” those you disbelieve. (I do some of that myself in what follows.) Still, if you approach the data with a relatively open mind, you may garner some insights that help you see more of what is actually going on on the court.

Nets, Old and New

Remember, these ratings capture average performance per 100 possessions. With as many injuries and absences as the Nets have had this season, just showing up is commendable. Nonetheless, guys who have played heavier-than-expected minutes will be penalized in the ratings if their performance has suffered as a result.

Kevin Durant (1349 minutes), +4.8. KD has dropped out of the MVP conversation, and not only due to missing time. He ranks 18th in the league in RPM, with about half the per-possession contribution of the top players, Jokic, Embiid, and Curry. Still, he has carried the offense (+3.7) and contributed on defense (+1.1) for a team without a lot of bright spots.

Ben Simmons (0 minutes), +3.7. Well, that was his rating last season in Philadelphia (+1.3 offense, +2.4 defense). Nets fans can only hope that he gets back to that level, and quickly.

Seth Curry (1822), +1.6. The Nets’ second-best player, pending Simmons’ availability, though most of that play was obviously with the Sixers. For all the talk of his defensive limitations, his defensive rating is excellent, +2.2. (That may be a statistical fluke; but his defensive rating last season was +1.7, so maybe it’s a trend.) How well will it translate to Brooklyn?

Kyrie Irving (546), +0.3. Kyrie is such a gifted offensive player that he can just step on the court and contribute superbly (+2.8). Defensively, not so much (-2.4). By comparison, in his prior two seasons with the Nets, his offensive rating was +3.4 and his defensive rating was -0.1. Will he be near that level by playoff time, despite having just a half dozen more dress rehearsals?

Andre Drummond (1052), +0.1. Another trade throw-in who looks more productive than most of the Nets’ holdovers. His excellent defense (+1.8) features a remarkable 24 rebounds per 100 possessions, but also 2.4 blocks and 3 steals. The main limitation on his playing time with the Nets may be his fit with Simmons.

Blake Griffin (908), +0.1. Despite his shooting woes (.508 true shooting, down from .610 last season), Blake rates as a surprisingly productive offensive player (+0.9). Misleading? Perhaps. Or perhaps veteran savvy, setting picks, and making the right passes matter.

Patty Mills (1930), -0.2. It’s very hard to complain about a supposed bench guy who has led the team in total minutes, by far, while playing productively. Surprisingly, he rates as one of the Nets’ better defenders (+0.6); but on a per-possession basis, his shots, points, assists, rebounds, and steals are all below his career averages, and his recent (fatigued?) performance has pushed his rating downward.

LaMarcus Aldridge (1004), -1.6. Aldridge has played a bigger role than most of us expected, and he is shooting well above his career rate; but his defensive limitations (-1.6) have become more glaring as the season has worn on.

Nic Claxton (583), -1.7. Many fans have come to recognize that Claxton is a liability on the offensive end (-1.0); he is a career .286 shooter from beyond three feet. Fewer fans have recognized how little a switchable defensive big adds to a team with so many other defensive holes—his defensive rating is a mediocre -0.7.

Bruce Brown (1219), -2.5. A good defender (+0.3) but often a black hole on offense (-2.7). Still, he’s looked energized since the trade deadline, so perhaps as the offense evolves, he’ll get back to last season’s less bad level (-1.0).

James Johnson (954), -3.6. Another vet pressed into heavy service due to injuries. He has some unusual skills, but has been an overall liability on both defense (-2.4) and offense (-1.2).

Joe Harris (423), -4.5. Harris’s rating is a reminder of the fragility of the metric when minutes are limited and unrepresentative (all from the first month of the season, mostly with the same lineups). Kinda doesn’t matter, now that he’s done for the season anyway.

The Rookie Ladder

“Why, oh why, doesn’t Nash play the rookies? They couldn’t possibly be worse!” Well, yeah, they could be. Minutes are very limited for Sharpe and Duke, especially. But based on what they’ve shown so far, none of these guys is really a productive NBA player—yet. RPM has no idea that they are rookies, yet it zeroes in on their “rookie mistakes,” especially on defense.

Day’Ron Sharpe (391), -1.8. How can a guy who looks like a stud and rebounds like crazy grade so poorly (-2.1) on the defensive end? 7.4 fouls per 100 possessions is a start. And garbage time features a lot of helter-skelter defense, which is probably not his strength.

Cam Thomas (1043), -3.2. Thomas has had some great moments, but we’re measuring production, not swagger or potential. Even with his recent “hot” streak, he’s shooting 27 percent from three. And even more than Sharpe, he’s given up much more defensively (-3.6) than he’s contributed offensively (+0.4).

David Duke (340), -4.0, Like the other rookies, Duke has been bad defensively (-1.9); but he’s been equally bad on the offensive end (-2.1).

Kessler Edwards (748), -4.8. Edwards’ defensive rating is not bad as rookies go, -1.3. Alas, the offense has been a whopping 3.6 points worse with him on the court. Perhaps that’s just a fluke; but he is 13th on the team in true-shooting—worse than Brown, Thomas, Johnson, and Griffin. The numbers suggest he has quite a way to go to become even a Brown- or Bembry-type bench contributor. Perhaps unsurprisingly, the talk of creating a spot for him on the playoff roster has quieted.

Some Ex-Nets

Gone, but not forgotten.

James Harden (1773), +4.7. Harden has gone on a mini-tear in his first games with the Sixers; but even as a Net he was a top-40 NBA player and, given KD’s absences, the most productive Net in terms of contributing wins. Fans’ complaints about his defense and turnovers were not wrong, but they were overblown.

DeAndre’ Bembry (991), -2.4. Not surprisingly, Bembry looks a lot like Brown, another undersized but scrappy, high-energy, defender. If anything, he may have been a bit less bad offensively (-2.5 versus -2.7), due to his uncharacteristically hot shooting. Wish him well, though not against the Nets.

Jevon Carter (615), -5.0. You thought he was bad. RPM agrees.

Around the League

The top ten players based on the current RPM ratings are Nikola Jokic (+11.3), Joel Embiid (+9.9), Steph Curry (+9.6), Giannis (+8.2), Tatum (+7.2), Chris Paul (+6.9), LeBron (+6.8), Luka Doncic (+6.5), Rudy Gobert (+6.2), and Donovan Mitchell (+6.1). That’s a pretty good indication that the numbers are meaningful, even if they’re noisy.

The top-rated offensive player is Giannis (+6.6), followed by Trae Young, Doncic, Mitchell, Curry, Lebron, and Jokic (+5.6 to +5.1), with Lillard (in limited minutes), Embiid, and Morant (+4.7 to +4.5) rounding out the top ten.

The top defenders are more closely bunched, with ten guys within a point of league-leading Jae Crowder (+6.3) and 15 with defensive ratings of +5.0 or better. Lots of familiar names, including Jokic, Capela, Looney, Gobert, and Horford. Also notable are two Cavs in the top 15, rookie Evan Mobley and Nets alum Jarrett Allen.

In most seasons, the top offensive performers are more valuable to their teams than the best defenders. That hasn’t really been the case so far this season. Perhaps that’s a result of COVID disruptions or rule changes—or perhaps the defensive ratings will begin to sag as the season wears on.