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. 

Watch LeBron James’ speech after getting his ring in Cleveland

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“At this point, if you’re not from here, live here, play here, dedicate yourself to Cleveland, then it makes no sense for you to live at this point — Cleveland against the world!”

And with that, the Q went nuts.

LeBron James and the Cavaliers got their rings and raised a banner in Cleveland — the first title banner in that city in 52 seasons (although the Indians are trying to have their say on the matter across the street). It was emotional for everyone in the building, and particularly the hometown boy LeBron.

Check out the full ring ceremony.

Best foot forward: 76ers’ Embiid set for long-awaited debut

Philadelphia 76ers center Joel Embiid (21) shoots against Memphis Grizzlies center Marc Gasol, of Spain, during the first half of a preseason NBA basketball game Tuesday, Oct. 11, 2016, in Memphis, Tenn. (AP Photo/Mark Humphrey)
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PHILADELPHIA (AP) With a dunk contest, half court shots and “Juju on that Beat ” dancing contest finished, Joel Embiid turned back toward Philadelphia 76ers fans at an open practice.

Instead of scurrying off to the locker room, Embiid stuck around for selfies with fans sitting on all sides of the court, stretching mobiles high over his 7-foot-2 frame to squeeze as many fans as he could into each snapshot .

Embiid even entertained in 1-on-1 games – against little kids.

Embiid has the joyous personality of a kid himself. Social media posts include him crushing on Rihanna or teasing an Australian-born teammate that he’ll get deported if Donald Trump is elected president of the United States. The 76ers posted a Vine last season of Embiid throwing down a between-the-legs dunk at warmups that blew up NBA-centric Twitter feeds and offered fans a fleeting look at the potential ahead.

“Philadelphia’s going to love him,” coach Brett Brown said.

The city has waited 29 months to love the 22-year-old Embiid for his impact on the court.

The Sixers have stripped the bubble wrap off Embiid and the No. 3 overall pick of the 2014 draft is set to make his debut Wednesday night against Oklahoma City after two foot surgeries, countless days of rehab, gallons of Shirley Temples and inherited expectations that he is the savior for a woebegone franchise that has made a farce of competitive basketball.

Embiid, who grew up playing soccer and volleyball and didn’t play basketball until 2011, is no longer the raw project out of Kansas. He’s grown 3 inches and beefed up to about 275 pounds to better handle the daily grind of battling the NBA’s biggest big men.

“Where I was three years ago, I’m not even close to what I am right now,” Embiid said. “My game has gotten so much better. The past three years, if you watch the game tape, I’m not the same guy.”

Embiid had a fantastic freshman season with the Jayhawks, averaging 11.2 points and 8.1 rebounds. He blocked 72 shots to earn Big 12 defensive player of the year honors.

He might have been the No. 1 overall pick in `14 – a spot that went to Minnesota’s Andrew Wiggins – had he had not suffered from a balky back and needed surgery for a stress fracture in his right foot shortly before the draft. Embiid, who knew only his native Cameroon before college, failed to really adjust to life without daily organized basketball. His weight ballooned, and he was booted from a road trip because of a petulant attitude. Part of his weight gain was blamed on a junk food diet washed down with that mix of ginger ale and a splash of grenadine garnished with a maraschino cherry commonly known as a Shirley Temple .

His personal life was rocked in October 2014 when his 13-year-old brother Arthur died in a car crash in Africa.

“It’s been really hard,” Embiid said.

Embiid was expected to anchor the rebuild in 2015 for a Sixers organization that had scorched their roster and abandoned a competitive season in hopes of gobbling lottery picks. But a second surgery of the navicular bone on the right foot in August 2015 cost him his sophomore season.

Embiid was devastated but handled his time off with greater seriousness in his workouts and a mission to return as a dominant center. The 76ers even shipped Embiid to a sports science facility and sports medicine hospital in Qatar to rehab.

“When I left college, I felt I wasn’t ready for NBA life,” Embiid said. “But since I’ve been in the league, the support I’ve had around me from (former president) Sam Hinkie, the coaching staff, they’ve just been on me. That’s what I usually need. When somebody’s on me, I can usually do better.”

The Sixers played it safe this year and held Embiid out of summer league. Brown, in his fourth season, entered training camp with a cautious plan to limit Embiid’s minutes and games when the schedule is packed.

Embiid, well, he left his training wheels in the dust.

He averaged 11.6 points over all seven preseason games. Embiid played 20 minutes a game as the preseason ended and Brown said he would consider playing his starting center more often. Brown would ideally lessen Embiid’s load early and help him avoid the same fate of other centers who had careers curtailed by foot injuries, like Yao Ming and Zydrunas Ilgauskas.

In the preseason, Embiid flashed some wow moments that had his teammates hooting and hollering on the bench. But Embiid sometimes tried too hard to be the showstopper and was a turnover machine.

“At times, he just reminds me of a yearling, trying to find his balance,” Brown said. “He wants to score. He wants to dominate. How about the passion he plays with? You can’t coach that. And he has `it.”‘

So who plays with him? The Sixers have had more key players out with injuries under Brown than they have had competing for playing time.

Ben Simmons, the No. 1 overall pick this year, is sidelined indefinitely with a broken bone in his right foot. Nerlens Noel, the No. 6 pick in the `13 draft, is out at least a month after surgery on his left knee. Starting point guard Jerryd Bayless is sidelined with a ligament injury in his left wrist. Jahlil Okafor, Philadelphia’s leading scorer and rebounder, is restricted as he recovers from surgery on his left knee.

The Sixers went 10-72 last season and have won 27 games in Embiid’s two seasons on the bench.

“Having to sit on the bench and watch us lose almost every night has been hard,” Embiid said.

Embiid took note of the hype that happened across the street during one of his visits to the Philadelphia Eagles sideline. Carson Wentz went from unknown rookie to whipping fans into a “Wentzamania” frenzy with his quick start.

“I think it’s our turn,” Embiid said.

WWE’s The Undertaker is at Cavaliers ring/banner celebration

NEW YORK, NY - AUGUST 23: The Undertaker recovers during his fight against Brock Lesner at the WWE SummerSlam 2015 at Barclays Center of Brooklyn on August 23, 2015 in New York City.  (Photo by JP Yim/Getty Images)

Remember during the NBA Finals LeBron James and a number of the Cavaliers players were wearing WWE star shirts? LeBron in particular wore an Undertaker shirt before Game 5, then had on The Ultimate Warrior shirt after Game 7.

Well, guess who is going to be at the ring and banner ceremony Tuesday night in Cleveland?

The Undertaker is there is full regalia — Cavs fans are going to love this.

Who was most excited to meet The Undertaker? The Birdman, of course.

(Hat tip CBSSports.com)

Carmelo Anthony, Chris Paul, other NBA stars talk “togetherness” in new video


Carmelo Anthony and other NBA players have talked about wanting to take the conversation created around the national anthem protests and turn that into action in their communities.

A new video featuring Anthony, Chris Paul, Kyle Korver, Dwyane Wade and other NBA stars is along those lines — it speaks to unity. It’s about we as a nation learning to talk to each other again — to listen and have empathy, not just talk at each other.

It’s a step. One of many we all need to take.