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. 

Really? Online petition started to change name of Durant, Oklahoma, to Westbrook.

OAKLAND, CA - MAY 30:  Kevin Durant #35 of the Oklahoma City Thunder stands on the court in Game Seven of the Western Conference Finals against the Golden State Warriors during the 2016 NBA Playoffs at ORACLE Arena on May 30, 2016 in Oakland, California. NOTE TO USER: User expressly acknowledges and agrees that, by downloading and or using this photograph, User is consenting to the terms and conditions of the Getty Images License Agreement.  (Photo by Ezra Shaw/Getty Images)
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Durant, Oklahoma, is a city of just more than 15,000 people in the southern part of the state. It is the capital of the Choctaw Nation of Oklahoma, and it was named after its Choctaw founder, Dixon Durant.

But some people in Oklahoma are not high on the name Durant, lately. Kevin Durant decided to bolt the Oklahoma City Thunder for the Golden State Warriors this summer, and some Thunder fans feel betrayed. Understandably. Durant was well within his rights, but if you’re a Thunder fan and you’re not hurt by this it would be strange.

Still, you have to hope what follows is satire. It reads like it.

Oklahoma’s Ryan Nazari created a Change.org petition asking the city of Durant be renamed the city of Westbrook. As in Russell Westbrook. The guy who signed a contract extension to stay in Oklahoma (for just one extra year, but still). Read the petition below and tell me it doesn’t sound like satire.

“Ladies and gentlemen, the great state of Oklahoma has been betrayed. As many of you know, Kevin Durant has left our state, torn out our hearts, and left our beloved Oklahoma City Thunder in depleted shape. All of this after even being offered a cabinet position for the State of Oklahoma. It is because of this heinous action that I believe the State of Oklahoma has a responsibility to change the name of the City of Durant to Westbrook, the man who is loyal, whom we believe in, and who will lead our team to glory. Yes, it is understood that the city Durant was not named after the evil Kevin Durant, but it is just another hideous reminder of what happened to our community.”

As of this writing, he had reached his goal of having more than 1,000 people sign on.

Maybe it’s satire, but it’s more creative than burning a jersey.

Obviously, the name of the city is not changing. If people want to live in Westbrook, they should move to Maine.

Way too early look: Who could make up USA’s 2020 Tokyo Olympic basketball team?

RIO DE JANEIRO, BRAZIL - AUGUST 21:  Jimmy Butler, Kevin Durant, DeAndre Jordan and Kyle Lowry #7 of United States stand on the podium after defeating Serbia in the Men's Gold medal game on Day 16 of the Rio 2016 Olympic Games at Carioca Arena 1 on August 21, 2016 in Rio de Janeiro, Brazil.  (Photo by Elsa/Getty Images)
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Let’s start with the obvious: This is an exercise in futility. There is no way to predict accurately what the 2020 USA men’s basketball team headed to the Tokyo Olympics will look like. There will be injuries that sideline guys. There will be contract situations where key guys decide it’s in their best interest to sit out. Plus, there could be a guy just now entering his junior year of high school who we don’t know well yet but in four years will be a clear choice for the team.

Now that we’ve gotten through the tedious disclaimer, let’s have fun:

What will the 2020 USA Basketball team look like?

First, it will have a bit of a business attitude — Gregg Popovich is coaching now. Not that Mike Krzyzewski ran a college party Team USA, far from it, but with Popovich’s demeanor and the scare put into the 2016 team (and some improving world powers, such as Canada), expect the USA to be a little more focused next time around.

For the roster, who from the 2016 gold medal team in Rio returns for more gold? At the top of the list: A 31-year-old Kevin Durant will be back for one more run (and to climb on top of the USA Olympic scoring list). He will be the unquestioned team leader. The alpha. It will be his team.

After that? Young stars who want one more go at it such as Paul George, DeMarcus Cousins, DeAndre Jordan, and Klay Thompson will seriously consider a return. Maybe Jimmy Butler. Those guys will have a leg up having Olympic experience and a commitment to the program.

After that, some big names that passed on Rio are going to suit up in Japan. There will be far less defection of top talent this time around — the fears around Brazil will be gone, and NBA players wanting to sell more shoes in Asia will be eager to sign up. I expect you will see Stephen Curry, Anthony Davis, Kawhi Leonard, Russell Westbrook, and maybe James Harden decide they are in for the next round. LeBron James said he felt left out and may consider a return, but he will be 35 years old with 17 NBA seasons on his body by that point, does he want to put his body through an international curtain call? Probably not.

Rounding out the roster, expect a few guys from this year’s USA Select Team — the team the Olympic squad practiced against in Las Vegas at the start of camp — to make the leap up (as Kyrie Irving and others did this year).

Who? That’s the hardest thing to predict, it depends on development. Guys to watch include Victor Olidipo, Justise Winslow, Devin Booker, Brandon Ingram, and Jabari Parker — some of them will be ready to make the leap.

One clue to the 2020 roster: Players that you see in China for the 2019 FIBA World Cup will be more likely to make the 2020 team. (Yes, the World Championships are now the year before the Olympics, welcome to more of FIBA’s wisdom, as is the fact the Cup qualifiers fall during the NBA/Euroleague seasons.) Guys from the select team now that head to China in three years and perform well in that setting will likely have the USA across their chest in Japan.

Whatever team we send will have the most talent in those games. The question is will that be enough?

Check out the Cleveland Cavaliers Top 10 plays from last season

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With athletes such as LeBron James and Kyrie Irving on the team, you know the Cleveland Cavaliers Top 10 plays of last season were going to have some special moments.

Yes, the block by LeBron and the stepback three by Irving that sealed the first Cleveland title in 52 years are on top of the list.

But there are some other ridiculous Irving handles and even a Timofey Mozgov dunk in there (a $64 million dunk, apparently).

Watch Spurs’ Dejounte Murray throw off-the-backboard alley-oop to himself in pickup game

Washington guard Dejounte Murray, center, dribbles the ball past Mount St. Mary's center Taylor Danaher (50) as Washington forward Marquese Chriss, right, watches duirng the first half of an NCAA college basketball game, Thursday, Nov. 19, 2015, in Seattle. (AP Photo/Ted S. Warren)
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Just a suggestion for rookie Dejounte Murray: Don’t do this in front of Gregg Popovich. You may not like his reaction.

That said, the Spurs needed to get more athletic this off-season — landing Pau Gasol certainly didn’t help that cause — so enter first-round pick Murray, who pulled this off in a recent pickup game.

Murray is going to be brought along slowly in a backcourt where Tony Parker and Patty Mills will be splitting time at the point. Murray is more of a combo guard and is going to have to shoot a lot better than he did in college (28.8 percent from three) to get some run. But this is a situation where the Spurs can groom him, bring him along slowly, and see if they have another draft steal.

He’s certainly got the athleticism.