David Berri on Adjusted Plus/Minus

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Way back in 2006, David Berri, Martin Schmidt, and Stacey Brook came out with a book called The Wages of Wins. It was supposed to be Moneyball for sports other than baseball, but for a lot of people, the book read like Moneyball with a serious chip on its shoulder. In a team game with lots of variables, Berri and his co-authors were confident in their regression-based assertions that  there were 90 players more valuable than Allen Iverson during the season that he won MVP, that scoring was vastly overvalued while rebounding was too often neglected, and Ray Allen had been just as good throughout his career as Kobe Bryant. 

The general feeling among a lot of hard-core basketball fans and analysts was that the Wages of Wins system, which relied only on box-score based statistics, couldn’t possibly accurately capture everything that made a player valuable in a five-on-five game. The logical extreme of that philosophy came in the form of Wayne Winston, the former stat guru for the Dallas Mavericks whose brainchild was adjusted plus/minus, which sought to measure a player’s value without using any box-score statistics whatsoever. As it turned out, he had some even more outlandish conclusions than Berri and co. did. He said that the Knicks should never have traded Tim Thomas, that Lamar Odom was better than Kobe Bryant, and that Kevin Durant wasn’t helping the Thunder win. 
After last weekend’s Sloan stats and analytics conference, David Berri has a short post up on adjusted plus/minus. Here’s the crux of Berri’s argument for box-score bases metrics over adjusted plus/minus:
JC Bradbury and I – in a forthcoming article in the Journal of Sports Economics — report that only 7% of a player’s adjusted plus/minus is explained by what a player did the previous season (oddly enough, unadjusted plus/minus has a stronger – albeit still relatively weak – correlation).  In other words, the correlation coefficient for adjusted plus/minus from season-to-season is below 0.30.   And when we look at players who switch teams – as Songaila did – we fail to find a statistically significant relationship. In contrast, any measure (PERs, Wages of Wins measures, NBA Efficiency, Win Shares, etc…) based on the box score will have a correlation coefficient of at least 0.65, and often these marks are above 0.80. 

Berri makes a solid point. He uses Darius Songalia as a case study for how inconsistent adjusted plus/minus can be, but he could easily have used Kevin Durant, who started the season as a posterchild for how plus/minus based stats could contradict box score metrics but is now an example of how elastic adjusted plus/minus can be from season to season. 

I’m a big believer in using advanced stats to gain knowledge about basketball, but it appears that both Berri and Winston have holes in their metrics. Berri’s box-score based metrics don’t necessarily reflect who was doing what helped his team win the game. For example, let’s say Matt Barnes plays great defense on Kobe for 20 seconds and forces him into a tough fadeaway. Dwight Howard then blocks out Pau Gasol and keeps him from getting to the rebound. The ball caroms off the rim and goes to Vince Carter, who collects the easy rebound. In Berri’s system, only Carter gets credit for doing something right on that play. 
Winston’s system would theoretically give Barnes and Howard most of the credit for the play above. However, the issue is that they could have radically different roles on a different team. With another team, Barnes might not be a starter or a perimeter scorer, but a stretch four who provides energy and outside shooting off the bench without giving much on the defensive end. Thus, he could have a radically different value with a different team. 
Advanced statistics in basketball are wonderful, but they are far from airtight. For the foreseeable future, the best approach with advanced statistics will be to use a number of different metrics and see how they inform each other rather than wait for one perfect formula to reduce contributions to a single integer. 

Wembanyama encore: 36 points, 11 rebounds, 4 blocks against Ignite

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Victor Wembanyama is for real.

And I don’t mean real tall, although he is that, too. Check out this image of him next to Rudy Gobert, who is a legit 7’1″.

Wembanyama is for real like a genuine generational talent — in his second game against the G-League Ignite he had 36 points, 11 rebounds, and four blocked shots.

That comes off his 37-point performance in the first meeting where he hit 7-of-11 3-pointers and had five blocks.

To be clear: That is 73 points, 15 rebounds, nine blocks, shooting 9-of-18 from 3 (and 22-of-44 overall) across two games against a good talent level. And he is 18 years old.

Everyone in and around the NBA has been trying to come up with player comps — Kristaps Porzingis, Ralph Sampson, Tim Duncan — but the reality is Wembanyama is one of one.

Scoot Henderson — the G-League guard projected as the No. 2 pick in the 2023 NBA Draft — played just five minutes in this game after bumping his knee while guarding Wembanyama. He was taken out of the game and X-rays found a bone bruise, he did not return. He is officially day-to-day the team announced.

Wembanyama and his Metropolitans 92 got the win in this rematch, 112-106.

Draymond Green not expected to miss any games, Warriors to handle discipline ‘internally’

2022 NBA Summer League - Golden State Warriors v New York Knicks
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Draymond Green is not expected to miss any games for punching teammate Jordan Poole during an altercation during practice, Warriors GM Bob Myers said Thursday.

That’s not to say he is escaping any punishment, it will just be handled internally, Myers said.

Green showed up at Chase Center and apologized to the team and then left, he did not practice with the Warriors, reports Monte Poole of NBC Sports Bay Area.

“Draymond apologized to the team this morning, Jordan was there in the room, I was there in room with the team, the coaches, the players and we heard that,” Myers said.

Whatever punishment the Warriors are handing down to Green, it will not include missing games, Myers said.

Coach Steve Kerr added, “I expect [Green] to return on Saturday and get back at it.” That implies a couple of days suspension, likely with a hefty fine.

Kerr was also quick to shoot down the rumors of Poole having an “attitude” around camp as he comes up on a massive contract extension. Stephen Curry echoed that, saying those reports are “absolute BS.”

The Warriors have seen their fair share of Draymond Green incidents over the years, and as a locker room and franchise they know how to move on from it. While this made headlines, the Warriors will shrug it off and move on.

Miami, Milwaukee have their eyes on Jae Crowder

NBA 2022 Playoffs - Phoenix Suns v Dallas Mavericks
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The Heat and Bucks don’t just have interest in the same player. They’re looking to replace the same player.

Two years ago, P.J. Tucker helped Milwaukee win their first championship in a half-century. Last season, he helped Miami lock up the top seed in the East and make the Conference Finals.

With Tucker in Philadelphia, both the Heat and Bucks are looking to fill the void with a different lockdown enforcer that can stretch the floor.

Jae Crowder and the Suns agreed that he won’t participate in practice as the team looks to accommodate his trade request. In a recent ESPN+ article, Zach Lowe made it clear that both Miami and Milwaukee are interested in pursuing a trade for Crowder.

“The Bucks have internal interest in Crowder as that Tucker replacement after getting into the recent Jerami Grant and Bojan Bogdanovic discussions, sources say. They will search all season for one more piece.

“The Heat have interest in Crowder too, sources say, but finding matching salary is tough until Dewayne Dedmon, Caleb Martin and Victor Oladipo become trade-eligible in the winter. Martin might start, and the Heat are optimistic Oladipo can play a huge role.”

Grant and Bogdanovic were traded to Portland and Detroit, respectively. The Heat may struggle to find a trade that works since Phoenix probably won’t want to take on Duncan Robinson’s contract. Dedmon, Martin and Oladipo will become trade eligible on January 15th.

Crowder has a history with the Heat, as he helped them make the NBA Finals in the bubble. He helped Phoenix make the NBA Finals two seasons ago and then helped them finish with the best record in the NBA last season.

LeBron says Wembanyama is an ‘alien’ and a ‘generational talent’

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There was a time when LeBron James was the “it” kid coming for the NBA — a freakish athlete like nobody in the league had seen. A player the size of Karl Malone with the quickness and skills of an elite point guard.

Now the “it” guy is Victor Wembanyama, the 7’4″ mold-breaking big out of France — and LeBron is impressed.

“Everybody’s been a unicorn over the last few years, well he’s more like an alien,” LeBron said after the Lakers’ preseason loss to the Suns in Las Vegas. “I’ve never seen, no one’s ever seen anyone as tall as he is, but it’s fluid and as graceful as on the floor…

“His ability to put the ball on the floor, shoot step-back jumpers on the post, step-back 3s, catch-and-shoot 3s, block shots. He’s for sure a generational talent. And hopefully he continues to stay healthy, that’s the most important for him personally, and as you could tell he loves the game. He was smiling a lot while playing the game last night. I think it was the two best players in the draft on the floor last night and they both did their thing.”

Wembanyama is projected to be the No.1 pick in the 2023 NBA Draft, just ahead of point guard Scoot Henerson, who scored 28 points with nine assists of his own leading his G-League Ignite to a win over Wembanyama’s Metropolitans 92. Wembanyama scored 37 points in the game, hit 7-of-11 shots from 3, had five blocks and a few other shots changed because of his length (7’11” wingspan) and the threat of his block.

Wembanyama and Henderson face off again tonight in a second game between the Ignite and Metropolitans 92 just outside Las Vegas in Henderson (9:30 p.m. ET on NBATV).

Wembanyama will play, with his agent telling ESPN there are no plans to shut the No.1 pick down to avoid injury and protect his draft status. “He’ll never agree to that. He wants to compete and get better,” Bouna Ndiaye said.

LeBron looked back on his time as the “it” player and said simply, “thank got there wasn’t social media” at the time. It’s a different world now, but game still recognizes game.

And LeBron recognizes it in Wembanyama.