Monthly Archives: September 2010

Expected Points: Team Edition

This is a follow-up to my Shot Selection and Efficient Scoring post from a few weeks ago. In that post I used the Expected Points Per Shot data calculated by Albert Lyu of ThinkBlueCrew to look at the scoring outputs of several of last years top scorers, from various locations on the floor.

After looking at these numbers for individuals, I wanted to go back to last season and take a look at the numbers on a team level. I know everyone is ready for the new season to start, moving ahead with previews and forecasts and the like. Call me late to the dance, but I still have some analysis of last season that I haven’t worked out of my system yet.

 Here is the explanation of my technique:

Another way to think of Expected Points Per Shot, is the average number of points scored on a shot attempt. For example, over the last 4 NBA seasons, factoring in makes and misses, a field goal attempt at the rim was worth an average of 1.208 points.

Using numbers from Hoopdata’s Shot Location Database, and the Expected Points Per Shot from Lyu’s post I was able to calculate what I am calling Expected Points per 40 Minutes (XPts/40). I began by calculating each players XPts/40 from each area of the floor. To do that I took each player’s per 40 minute field goal attempts from each area of the floor and multiplied it by the expected Points Per Shot for that location. Adding these categories together results in XPts/40. Another way to think about this is, given a player’s per 40 minute shot selection, how many points would he score, shooting the average percentage from each location. The numbers I borrowed from Lyu are below:

  • At Rim – 1.208
  • <10ft. – 0.856
  • 10-15ft. – 0.783
  • 16-23ft. – 0.801
  • 3PT – 1.081
  • I needed to include Free Throws, so I used 0.759 the league average for last season.

In this post we are going to use the same technique and apply it to each team’s per game shot selection from last season. This whole exercise is just another way of looking the relationship between a team’s FG% and the league average from different areas of the floor. I like using the statistic of Expected Points as a more explicit example of what teams are losing or gaining with their shooting percentages. Instead of expressing the difference in FG% points, we can express it in actual points, making the results a little more tangible. Below is the Expected Points Per Game, Actual Points Per Game, and Points Per Game Differential for each team last season.

These numbers are not pace adjusted, so there is not tremendous value in comparing the XPPG and Act. PPG numbers. I do think that the Point Differential is a great illustration of a team with an efficient offense. The next graph shows the same numbers but broken down by floor location.

A few thoughts:

  • Only 10 of the 3o teams scored at a rate below expected on shots at the rim. However 6 of those 10 teams, (Charlotte, Chicago, Detroit, Houston, Milwaukee, New Jersey) were significantly below expected, a point per game or more. The different between the best team in the league, Cleveland, and the worst team in the league, Houston, was a total 5.149 points per game.
  • Oklahoma City was scored at a rate very close to expected on shots close to the basket. They were noticeably below average on long jumpers but almost completely offset this loss of points with their terrific free throw shooting, picking up an extra 1.227 points per game more than expected at the line.
  • Dallas’ efficiency on long range jumpers stands out remarkably in this analysis. They scored 1.418 more points per game than expected on jump shots from 16-23ft. This number is simply incredible. Only 9 of the other 29 teams scored more than expected on shots from this range last year. Dallas’ number is almost a full point better than the next two closest teams Toronto and Golden State. This amazing efficiency can be largely attributed to Dirk Nowitzki, Jason Terry and Caron Butler, who all shot better than 45% from this area on more than 4 shots per game.
  • Phoenix’s excellent 3PT shooting was worth an average of 3.350 extra points a game versus the expected rate. The Knicks were among the league leaders in 3PTA per game, but their poor shooting cost them an average of 1.022 points versus the expected rate.
  • Teams with up-tempo offenses, Phoenix and Golden State, were among the leaders in Point Differential. They were not alone, as teams with slower more deliberate offenses like Boston, Orlando and Utah also scored significantly more than expected.

Having now looked at this statistic from an individual and team perspective, I was curious what the relationship might be between the two. It would seem that certain players are responsible for large portions of their team’s performance in this metric. For example:

  • Last season Dirk Nowitzki scored 3.255 more points than expected per 40 minutes. Playing 37.5 minutes per game, he’s almost completely responsible for the 3.566 points per game more than expected that Dallas scored last season.
  • In the least surprising analysis of this post, Kevin Durant was very important to the Oklahoma City offense last season. Durant scored 2.712 more points than expected per 40 minutes. Without Durant’s scoring output, in his 39.5 minutes per game, the Thunder would have scored 2.3654 points less than expected per game. Both the quantity and quality of his free throw shooting contribute heavily to this scoring advantage.
  • Tyreke Evans had the lowest differential in my individual player analysis, scoring 1.9247 fewer points per 40 than expected. Playing 37.2 minutes per game last season, Evans bears a large share of responsibility for Sacramento scoring 2.070 fewer points per 40 than expected. I am not implying that Sacramento would be better off with someone else on the roster taking shots from Evans, but his poor shooting from several areas on the floor cost his team almost 2 points per game.
  • The Phoenix Suns were the team with the biggest positive difference between their expected points per game and their actual points per game, 7.264. Steve Nash’s shooting is responsible for nearly half of this total, as he scored 3.331 more points per 40 than expected. It goes without saying that his ability to create quality shots for his teammates is likely responsible for the rest of the Suns’ scoring more than expected.

As we head into next season I’ll be trying to keep these numbers posted, current and updated on a fairly regular basis. It will be interesting to watch the performance of both individuals and teams in this area. I am guessing that some of the player movement from this summer could have a huge effect.

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LeBron James, The Lisan Al-Gaib?

The Desert Planet Arrakis

This summer, as LeBron James announced to the world, and the children of the Greenwich Boys and Girls Club, that he was taking his talents to South Beach, I was in a sleeping bag, inside a tent, next to the Middle Fork of the Salmon River in The Frank Church Wilderness in central Idaho. Needless to say it wasn’t until several days later, as our backpacking trip wrapped up, that I heard the news, coverage and opinions about his “Decision.” With the circus in full swing by the time I reached my computer, I have held back on offering any of my own opinions. 

I have at various times agreed with almost everything I have read; which has created quite a set of contradictions within my thinking. LeBron has every right to make the decision that is best for his own life. I can’t honestly say that I wouldn’t have made the same choice if placed in his position. However, the choice certainly reveals something about his character. It revealed something about his character in the same way that Lance Stephenson throwing his girlfriend down the stairs reveals something about his character. There is certainly more to Lance than the piece of his character that led to that act, just as there is more to LeBron’s character than what led to him choosing Miami. Every choice that we make everyday, large or small, reveals some piece of our character.

The part I have pondered the most is what piece of LeBron’s character was revealed by this choice. LeBron’s decision to go to Miami has been used at different times to argue that he is a quitter, immature, oblivious, an ego-maniac, and a sidekick. Last night I came across a quote which I think addresses this question in a very concise manner, and completely clarified my thinking. 

Greatness is a transitory experience. It is never consistent. It depends in part upon the myth-making imagination of humankind. The person who experiences greatness must have a feeling for the myth he is in. He must reflect what is projected upon him. And he must have a strong sense of the sardonic. This is what uncouples him from belief in his own pretensions. The sardonic is all that permits him to move within himself. Without this quality, even occasional greatness will destroy a man.  

– Frank Herbert, Dune 

The quote is from the classic science fiction novel, Dune, by Frank Herbert. The qu0te concerns a messianic off-world prophet, whose coming was foretold in a prophecy by the people of the desert planet Arrakis. The people of Arrakis have awaited his arrival for centuries. The prophet, known as the Lisan Al-Gaib, arrives on the planet as a 15-year-old boy, unaware of the prophecy or the destiny the local residents expect him fulfill. 

The parallels to LeBron James leapt off the page and wrestled me to the floor. Since junior high LeBron has lived his life as the central figure in a modern myth. He has participated in perpetuating this myth to various degrees at different times, but I would argue that the myth-making is largely out of his control. Like the stories of Robert Bly and Sam Keen, a mythical template has been applied to a modern human being. As he was moving through his adolescence, the phase of one’s life where an identity is developed, he was dubbed “The King,” and we, with some minor prompting, willingly assumed the roles of “Witnesses.” 

What LeBron’s choice this summer has revealed more than anything, is that he doesn’t have a feeling for the myth he’s in. He appears to lack that sense of the sardonic. As his life merged deeper with the mythical template, he either lost or never developed an awareness, that this myth was a construction of the people around him. The myth represented our projections and was not necessarily a reflection of his actual life, actions or attributes. 

When he choose to leave the mythic template, due either to ignorance of the truth of the myth or because of a disregard for the value of it, he brought on scorn, ridicule and derision. But there may, however, be an unexpected escape for LeBron. All the scorn, ridicule and derision is directed not at LeBron the person, but at LeBron the mythic persona. This is because very few of the people offering opinions on this matter actually know LeBron the person. We know LeBron the myth, a myth we have all had a hand in creating. As I see it there are three ways out of this situation. 

  1. LeBron can reach a realization of the division between himself and his mythic persona. If and when he realizes this division, he can continue with his life seeking happiness from intrinsic sources, ignoring the public repercussions of his actions and resulting damage to his mythic persona.
  2. LeBron can, through play on the court, public relations savvy, and plenty of help from willing and unwilling NBA fans, create a new persona for himself as part of a new mythic template. Perhaps he will become a villain. Perhaps the public scorn will create an opportunity for him to become a martyr and adhere to that template. Perhaps he will struggle in Miami and be presented with an opportunity to return to Cleveland as part of the prodigal son template.
  3. LeBron can continue as he seems to have been, unaware of the true nature of his myth and that the power for myth creation doesn’t lie with him but within the fans. He can struggle against this, desperately clinging to a persona which due to his own choices is no longer available to him.

Mine is certainly a very convoluted opinion on LeBron James, and I am sure many will disagree with the situation as I see it. One fact that I believe we can all agree on is the first line of the Herbert quote: Greatness is a transitory experience. LeBron has been immersed in greatness for the better portion of his life, and it remains to be seen what sort of experiences he will have with greatness in the future.

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