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. 

This is why Shaq says he knows Kobe respects him (VIDEO)

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Do Shaquille O’Neal and Kobe Bryant hang out these days? Probably not.

But do the to respect each other? The answer, apparently, is yes.

During an interview for Oprah Winfrey’s OWN network, O’Neal said he knows that Kobe respects him because of a certain play. That play?

Prepare yourself for this one Portland Trail Blazers fans: it’s the famous alley-oop with 41 seconds left from Game 7 of the 2000 Western Conference Finals that put the Lakers up by six points.

That play was the exclamation point on an impressive fourth quarter, one in which the Blazers went hilariously ice cold from the field while the Lakers made up a huge deficit.

Here’s how Shaq tells the story:

Game 7. We’re down. I’m telling Kobe ‘Hey man, I’m open’.

[And Kobe responded with] I got you.

He crosses up Scottie Pippen, and he catches eye contact with me like, ‘OK this is the one you wanted.’

He throws it up super, super, super high. I have to go up and get it and throw it down. Puts us up by five [it was six] and I know we’re going to win, we’re going to the Finals.

If you go back to the footage after we win [the game] who jumps in my arms? Kobe Bryant.

Meanwhile, a 12-year-old Dane Carbaugh’s heart still aches from that game.

Carmelo Anthony lands in OKC, gets greeted by fans at airport (VIDEO)

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Carmelo Anthony is now a member of the Oklahoma City thunder.

Man that is still really weird to type.

But this has been an insane offseason, and nevertheless the former New York Knicks forward is now a teammate of Russell Westbrook and Paul George.

We are not sure how these teammates are going to play together next season given their propensity for high-usage play, but we are definitely all ready to watch it very soon.

Meanwhile, Anthony was greeted by fans in Oklahoma at the airport after arriving to be with the team.

Via Twitter:

Do you think this will get Carmelo to stay in OKC?

Guess we will just have to find out.

Cavaliers are frontrunners, but where will Dwyane Wade land?

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Dwyane Wade and the Chicago Bulls reached a buyout agreement — he will take an $8 million haircut to become a free agent. Not that we should feel bad for Wade, I wish someone would pay me $15 million to go away.

The next question: Where will Wade play this season?

The smart money is on Cleveland, but it’s not that simple. Adrian Wojnarowski of ESPN got the ball rolling, but others chimed in.

OKC is an interesting option on the court, if their ownership group is willing to eat a little more tax to make it happen (the Thunder would pay about $24 million, based on their current payroll). Alex Kennedy of Hoopshype shed a little more light on that and other options.

It’s probably going to be the Cavaliers — his good friend LeBron James is there, they are the best team in the East so a trip to the Finals (and a shot at a ring) are very possible, and he could start for them. That’s probably enough to get the deal done.

Expect Wade to take a little time with this decision. Veterans are not big fans of training camps, he may be willing to miss a little, spend some time with the family, listen to pitches, then choose Cleveland where he wants to play this season.

 

AP source: Bulls agree to 2-year deal with Mirotic

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CHICAGO (AP) A person with knowledge of the situation says the Chicago Bulls and forward Nikola Mirotic have agreed to a two-year contract that could pay as much as $27 million.

The person spoke to The Associated Press on the condition of anonymity Sunday because the deal has not been announced. The Bulls hold an option on the second year.

The 6-foot-10 Mirotic averaged 10.6 points last season. He has scored 10.8 per game over three seasons.

The Bulls are rebuilding after winning 41 games and losing in the first round of the playoffs. They traded All-Star guard Jimmy Butler to Minnesota on draft night for three players 23 and younger – Zach LaVine, Kris Dunn and the rights to No. 7 overall pick Lauri Markkanen.

Yahoo Sports first reported the agreement.

More AP NBA: http://www.apnews.com/tag/NBAbasketball