Last week I posted a comment on the Orlando Magic’s signing of Rashard Lewis. This comment noted that Lewis might be worth his hefty contract (he signed for the league maximum) if he plays small forward. But if the Magic play Lewis at power forward – which they might be inclined to do if they truly pass on Darko Milicic – then the production offered by Lewis will be worth far less than the wage he is paid. In sum, the Magic can do much to justify the wage Lewis is paid by simply keeping Lewis at small forward.
Yglesias Disagrees
This analysis led to the following statement from Matthew Yglesias:
This is more than a little perverse. Good power forwards are hard to come by. That Rashard Lewis is capable of performing competently in that role is an asset he has as a player. But thanks to the WoW position-adjustment method, it registers as a problem for his game. If he was much, much worse at playing the 4, he’d never be asked to do it, and his WoW rating would look much better. But in the real world, he’d be a less valuable basketball player.
Where to start with this statement?
1. As I will demonstrate in a moment, Lewis is not a “good” power forward.
2. Lewis is capable of being an average power forward. But Lewis is being paid the league maximum. For a player to collect this kind of money and only be “average” suggests a problem.
3. The idea that Lewis would not be asked to play power forward if he is much worse at playing this position runs counter too much of the evidence we present about basketball in The Wages of Wins. Just a quick counter-example: Eddy Curry is not a competent center yet he is asked every night to play this position.
Beyond these points, Yglesias appears to be arguing that Lewis should be given extra credit for being able to play two positions.
Back to the Numbers
Let’s go back to the numbers and see the problem with the Yglesias “extra-credit” argument. The following table reports a side-by-side comparison of Lewis to both an average NBA small and power forward.
Relative to the average small forward, Lewis is above average with respect points scored, rebounds, turnovers (he has less than an average small forward), and shooting efficiency. Given these marks, it’s not surprising that Rashard’s WP48 – when he is compared to a small forward — is well above average.
When he shifts to power forward, though, he should now be compared to the average at this position. Again he is above average with respect to points scored, turnovers, and shooting efficiency. But his ability to rebound is well below the mark we would expect from an average power forward. Consequently, when Lewis plays power forward, his lack of rebounding hurts the team.
An average NBA team captures nearly 42 rebounds per game. Nearly 24 of these, or 57%, come from power forwards and centers. When you put a player at this position who rebounds at a below average rate, a team’s chances to win are diminished.
Yglesias, though, wishes to give credit to Lewis for at least making the effort to play power forward. This strikes me as very much the same argument people offer in defense of Allen Iverson. The Answer takes a large number of shots, many of which miss the mark. People argued, though, that Iverson should get credit for “creating his own shot” or making the effort to take these shots. Following this argument, it must be the case that Wins Produced minimizes the “true” value of Iverson since players are not given credit in calculating Wins Produced for just taking shots. For a player to create wins, shots taken must actually go in the basket.
The validity of the Iverson argument was undermined by what we observed last season. The 76ers traded Iverson to the Denver Nuggets for Andre Miller. When we look at shot attempts on this team both before and after the trade we see little difference. In other words, Iverson didn’t so much “create shots.” Rather, he simply took shots his teammates were more than capable of taking. Furthermore, we saw before the trade that Miller had consistently been more productive than Iverson in terms of Wins Produced. Consequently, despite warnings that the 76ers were going to suffer without The Answer, I argued the team should dramatically improve. And this is indeed what happened.
Now we have the argument that the value of Lewis should not depend upon position played. The numbers tell us that playing Lewis at power forward will cost Orlando rebounds. But we should ignore this fact and simply give Lewis extra credit for making an effort.
Unfortunately, the numbers tell us a different story. If you play Lewis at power forward his team will suffer with respect to rebounds. And when rebounds decline, teams tend to win less.
In sum, position played matters in the evaluation of NBA talent. Centers and power forwards offer a different set of statistics than small forwards. Small forwards are different from guards. Given these differences, how much a player is helping a team win depends on the position the player is playing. To evaluate a player’s contribution these position differences have to be considered. If not, the contribution a player makes to team wins will be estimated incorrectly.
Metrics Without Position Adjustments
Although I should stop writing today and get to my “real” work, I want to make one more point about position adjustments. Metrics like NBA Efficiency (which is similar to TENDEX and Points Created) and John Hollinger’s Player Efficiency Rating (PER) do not have a position adjustment. This is because scoring dominates these measures (there is a strong correlation between a player’s NBA Efficiency and his scoring totals). And because scoring rates do not very as much by position, one does not have to adjust for position played when looking at NBA Efficiency. A similar argument applies to PERs.
Unfortunately, as noted last fall, both PERs and NBA Efficiency have a problem with inefficient scoring. Basically, a player can score inefficiently but raise his PERs and NBA Efficiency marks by simply taking more shots. Having inefficient scorers taking more shots does not help a team win, hence these metrics do not always evaluate a player’s contribution to team success correctly. Specifically, these measures tend to lead people to think that players like Allen Iverson and Carmelo Anthony are truly great players. In reality, though, both Iverson and Anthony are closer to the league average in player productivity.
Back to Lewis
Average is also how one would describe Rashard Lewis when he plays power forward. Just like it is not good enough to simply take shots in the NBA, it’s also not helping much to play a position as well as an average player. At least, if you are receiving the maximum salary, people should expect more from you than simply average production.
Basically, there is no “free lunch” in the NBA. You do not get extra credit for taking shots that don’t go in. You also don’t get credit on the scoreboard for playing out of position. At the end of the day, you win because your numbers beat your opponent’s numbers. And if the Magic do end up giving Lewis significant time at power forward, Orlando is going to find that their numbers – and their team wins – are going to suffer.
– DJ
Westy
July 9, 2007
While playing Lewis at PF may not help his team, it would seem to help his personal statistics. As you state, an average team garners 42 rebounds. Without another PF on the floor, Lewis is more likely to get a rebound, thus inflating his personal Win Score, even if he’s less adept than a great PF at garnering said rebounds. Therefore, he may look to be a better than average SF precisely because he does play several minutes at PF. It is difficult to speculate whether other SF’s would also be able to attain higher rebounding numbers with relatively unaffected scoring if they also got the chance to play PF.
Due to floor positioning, the positions close to the basket are inherently more likely to get rebounds. Therefore, while not helping the team win, individual players who are moved ‘up’ one position it seems may experience an advantage based on Win Score due to the importance of rebounds in its formulation (why the PF’s and C’s have the highest Win Scores).
It would be interesting to compare Lewis’ own actual numbers when he’s on the floor as the PF versus as the SF. If they vary, it would indicate an individual’s own Win Score varies based on where on the floor they’re playing.
dberri
July 9, 2007
Westy,
Okay, I went and looked at 82games.com. They have time each player played at each position. My sense is they look at this on a game-by-game basis so their position measures should be more accurate than mine (I look at the end of season numbers). Interestingly, there numbers seem to match mine.
But that is not the issue. You are arguing that when Lewis plays more at power forward his rebounds rise. There appears to be some evidence of this. In 2004-05 and 2005-06 Lewis played almost entirely at small forward. His rebound numbers were also lower. In 2002-03, 2003-04, and 2006-07 he played more at power forward and captured more rebounds. It does not appear to be a huge effect, but there is something there.
I would emphasize that in all five seasons he was below average in rebounding for a power forward. So although it might be the case the Lewis can increase his rebounds when he shifts to four, I do not think the effect is large enough to justify paying him a maximum contract to play this position. The Magic would be better off finding other players to play power forward and center and keeping Lewis at small forward.
Let me also add that at one point I looked at how changing position impacted performance and I did not find a statistical effect. I would like to do more research on this, but I do not think you can simply change a player’s position and dramatically change what he does on the court.
Rasta
July 9, 2007
The argument that Lewis can’t rebound as well as other PFs is flawed. According to Berri’s table, Lewis is outrebounded by PFs by 3.3 boards per 48 minutes. However, if you look at 82games’ positional data, he actually performs much better. Per 48 minutes, Lewis is outrebounded by 0.2 boards (10.5 minus 10.3 rbs/48).
The error, I believe, is caused by solely looking at Lewis’ total stats instead of looking deeper into the positional stats.
If you look a little bit deeper, you’ll see that Lewis outperforms his man no matter what position he’s playing.
dberri
July 9, 2007
Rasta,
Not sure I disagree with your numbers. But I would emphasize the point I am making. Lewis is being paid a maximum salary. So he can’t just be as good as an average power forward. He has to be much better to justify that wage.
Chirstopher
July 9, 2007
The numbers from 82games are here: http://www.82games.com/0607/06SEA9C.HTM
But what is really odd here is the time Lewis played as center. Here his 48-min averages are 24.5 ppg and 19 rpg! I understand the points raised here but this seems like fiction. In any event, from what I’ve seen as a fan Lewis gets moved to the 4 for smallball which might introduce all matter of issues (e.g., is a 4 really la 4 then). I totally understand that position is important but am not sure that a simple adj linked to 1 – 5 is the right answer. It seems like so many players play multiple positions these days. I remember when LeBron James came out and I was playing fantasy ball. He was listed as a PG, SF, PF. And when Boris Diaw had his first year with he was listed as every position but point guard.
MT
July 9, 2007
I tend to agree with Dave that Lewis, specifically, is much better as a 3 than a 4 but that comes from anecdotal visual observation and not statistics. I would note in his and all players’ defense, that he has no say in what positin he plays and being played out of position may reflect only on his team’s poor personnel decisions at the PF or bad coaching. I believe it is correct to infer that, when played full time at his optimal spot, he will perform best and to the extent he is played out of position,he will disappoint.
I think, on the broader point, there is to some extent a difference that is either one of semantics or of confusion as to purpose. Or perhaps an outright disagreement about purpose. The versatility of a player should logically have value in my view. I think the WoW approach focuses on productivity in the past and argues for inferences to be drawn for the future, but does not purport to capture any value from versatility, which I tend to think of as akin to an option. If I buy a convertible bond, it is both a bond and an option. It may perform well as a bond but ultimately the option may never deliver added proceeds. Still, when making the decision to buy and what price to pay for it, the option has value. If I can play Lewis either 40 minutes at the 3, or 30 minutes at the 3 and 10 at the 4, it frees me up to shape my roster by selecting the best backup 3 or 4. I don’t have to limit myself to looking at backup 4. Also, I have a built in hedge against injury risk to my other 4’s. All these have value in the future.
To some extent, I think the differences in view on this issue flow from either explicit differences / semantic differences / or simple confusion over whether one is opining about someone’s past productivity, in which, by analogy, all options have been exercised, or his present value (or future value) in which case there should be some value accorded to the option to play different positions.
Joe
July 9, 2007
Lewis playing some power forward could help his team by taking time away from a below average reserve PF. That’s not a huge factor though.
Troy
July 9, 2007
MT, I think you’ve got it exactly right above. The fact that Lewis is a very good small forward and at least a mediocre power forward is a positive overall for his team. It gives them more flexibility, especially in the case of injury — at least they can give some of those minutes to a mediocre power forward (Lewis) rather than one of the guys on the end of the bench who may be a well below average PF.
This only becomes a “problem” if the team chooses to use Lewis for huge minutes at the #4 spot when they have at least an average or slightly above average alternative. I believe that’s closer to Matt Y’s original point — it seems unfair to Lewis that his near-competence playing out of position at the #4 spot seduces coaches into using him too often at that spot.
A question this raises for me is, “Does the SF position ever deserve max money, given that the ability for an average player at that position to produce wins is lower than for other positions?”
Jason
July 9, 2007
I’ve struggled with the notion of positions and their importance. What’s clear is that certain tasks need to be accomplished and some players accomplish more than others. Certainly the scoreboard doesn’t care if you’re a 7 foot center or a 6′ point guard scoring a bucket and it doesn’t care what hypothetical position Rashard Lewis will be considered have played when he scored a bucket. But WP cares, and it seems it cares because it assumes that all positions are equal and there’s an expected average output for each position that is equal in terms of its contributions to a win.
I think that this axiom needs to be examined a bit as it does not need to be true. Certainly the distribution of heights suggests that there are fewer potential 4’s and 5’s and thus it may be that substandard athletes will get more minutes in these positions. If true, the standard deviation on performance at these positions should be greater and some teams will have a harder time getting the assumed average output and may do better going with another strategy.
Most or all of this compensation seems to come from Lewis himself. The comparison of his averages for the season don’t tell this story, but again, if the 82games.com stats are to believed, in the minutes that he played PF, he was a better scorer, better rebounder, and took fewer shots (though more FT attempts) to get these points. They provide per 48 averages for all of the Win Score stats by position he played. (I’ll exclude center because the number of minutes he played there are unlikely to be statistically significant.) By my quick (read: possibly errant) calculations, his per48 Win Score as a ‘3’ was 8.8, while as a ‘4’ he produced 12.8 per 48. On a per minute, this means he was at .183 and .267 at the two positions. If the averages of .152 and .215 are to be used for calculating the average production, his production, relative to the average was actually better as a ‘4’ than as a ‘3’. Since the limited supply of potentially adequate (to say nothing of above average) 4s should be lower than the same for 3’s, if Lewis can improve relative to the average when he slides over, it’s probable that a replacement closer to the average 3 can be found easier than a replacement 4. Given that the 82games stats suggest that the Sonics did better in terms of net points while he played the 4, it further suggests that this may be the case. It may be that the Sonics picked their moments to put him at the 4 when the matchups favored him being a better rebounder, or something else was favorable, but no matter, it looks, from the statistical breakdown, that Lewis at the 4 *can* be a more successful strategy given the opportunity for him to improve his personal stats in this capacity and the likelihood of a better sub coming in at the 3 than at the 4.
What’s clear is that the stats for the team need to be there. What’s not clear is that it matters who gets them, though wins produced does care when it comes to crediting the success of a team to its individual players.
TK
July 9, 2007
More agreement with MT and Joe. Being flexible enough to fill in occasionally at another slot seems like a big benefit, both in terms of WinScore and anecdotally.
In terms of WinScore, it can mean avoiding big minutes for a really substandard backup PF by shifting Lewis over and putting a decent SF backup in the game.
But I have to say, it works much better — both anecdotally and in terms of WinScore — when the flexibility is to move down a position instead of up. As discussed a few weeks ago, Magic Johnson being able to run the point at 6’9″ means that he gets far more boards than a typical point. And Scottie Pippen working as a Point Forward means that the Bulls were never forced to give major minutes to a really substandard backup point guard. (If memory serves, Darrell Walker was essentially the unused backup point guard on one of those early championship teams, averaging basically zero minutes a game.) Instead, Pippen runs the show and a better backup SG or SF comes in. That *downward* flexibility is huge!
JChan
July 9, 2007
Great comments all around, in the post and the following comments. I don’t really have anything significant to add to that discussion, but I think the position adjustments are something that need to be explored more and more. It seems like most arguments I’ve seen against the WOW methodology attack the position adjustment as a weak spot.
Is there another way to present this so that people who have just discovered WOW don’t get turned off right away by the “magic numbers” of the position adjustment? And is there an easy way to decide on adjustments for multi-position players? It seems like until these questions have quick simple answers, then a good portion of the public will not take the time to see the wisdom in the method.
Or maybe do we accept that not everyone will agree with the WOW method and not worry about it? I’m rambling, but the position adjustment has always seemed to me to be the sticking point for wide acceptance.
Col Bat Guano
July 9, 2007
He still isn’t going to play any PF with Orlando no matter how many times you say it. I don’t even know where you got statistics for him playing PF for Seattle since he rarely did it and only when playing small ball.
MT
July 10, 2007
Working off a box score makes granular analysis hard. I would expect that individual teams do this kind of analysis all the time, just as they should track FG% based on shot selection, or whether a player scores going right or left.
(That reminds me of a funny story in Pistol that illustrates the limits of analysis of athletes based on past performance: an opposing coach noted before his first game against Maravich that Maravich was always going right and scoring. So he told his team, force him to his left. They did, all night, and Maravich went left all night. For 55 points.)
One modeling idea I’ll throw out is to create 2 or 3 tiers at each position based on minutes played at the position. KG might play 36 minutes at the 4. Leon Powe might play 2. Rather than evaluating all the other 4’s based on an average of a range that includes both of them, if they were tiered into 2 or 3 groups, it would enable full time 4’s to be measured against other full time 4’s, backup 4’s to be measured against backup 4’s, and perhaps allow for players to be gauged at each of their multiple positions. Also, tiering would address the (admittedly minor) issue of outliers who get garbage minutes.
Neil the Ethical Werewolf
July 10, 2007
I’ve read Yglesias’ response to this, and it seems fairly convincing. A good small forward should get credit for being average rather than terrible at other positions, because there will be situations (injuries, fatigue) when the alternative to moving Lewis to PF will be playing someone terrible at PF. Maybe you also have a fairly good SF to fill in for Lewis. Then Lewis’ average PF skills actually give you a better collection of players on the floor.
Rasta
July 10, 2007
I’ve got several comments to make, but not much time. I apologize in advance if I’m unable to make my point clear.
I understand (and generally agree with) the positional adjustment to determine a player’s marginal value versus an “average player”.
In this case, Dave Berri has taken Lewis’ total stats, and compared them to the “average SF” and “average PF”. Looking solely at rebounds, Lewis’ 8.1 rbs/48 is higher than the average SF (7.6 rbs/48), but lower than the average PF (11.4 rbs/48).
The problem with approach is that Lewis’ 8.1 rbs/48 is really the the combination of all the rebounds he grabbed while splitting time between SF and PF. By the way, using 82games data, it appears that Lewis played 1771 minutes at SF, and 576 minutes at PF.
So how did his rebounding stats look while playing those positions?
At SF, Lewis grabbed 7.2 rbs/48. At PF, he grabbed 10.3 rbs/48. This paints a somewhat different picture when comparing to the “average” players.
However, why stop there? Why should we compare Lewis’ stats against an average NBA SF or PF when we have data that shows how he performed against the player he was actually guarding?
This gets into an entirely new issue which I’d prefer to save for another day. Anyway, for comparison, here are the rbs/48 for Lewis, his man, and Dave’s average player:
At small forward:
Lewis 7.2
His man 5.7
Average 7.6
At power forward:
Lewis 10.3
His man 10.5
Average 11.4
At you can see, Lewis out-rebounds his man at SF, while holding his own versus PFs.
Based on this comparison, I don’t think it’s fair to say that Lewis’ rebounding (or perceived lack thereof) hurts his team.
Tball
July 10, 2007
A baseball parallel would be moving Piazza to DH/1B or Nomar to first base. They may be able to put up the numbers to get by at the new position, but Piazza and an average DH/1B contribute more to a lineup than Piazza and an average catcher. If we assume the forward playing along side Lewis is average, would you rather have Lewis playing an average PF role along side an average SF or Lewis playing a superior SF role along side an average PF?
I do think Lewis’s ability to play PF should be awarded some value, not unlike Hines Ward’s ability to be an emergency QB for Pittsburg or Troy Brown being able to fill in at cornerback – it provides situational flexibility, but it is a bad sign if you need to go to that well regularly.
Westy
July 12, 2007
Good posts. The issue of position adjustment is certainly the seemingly glaring reason Wins Produced is experiencing some hesitation in acceptance, JChan. As Rasta indicates Lewis’ own stats (rebounding) changed based on the position he was changing. While his aggregate totals were better than an average SF, his total while actually playing SF was less than average.
The issue seems to be that while PAWS evaluates each player against his own position the basis is Win Score, and with higher scores at PF and C, Berri seems to be arguing that those positions contribute more to wins.
On the basis of their Win Scores alone, fielding a team consisting of Garnett, Duncan, Howard, Lee, and Boozer would win the NBA championship. Lacking any guards or small forwards, that seems highly unlikely, though. Thus, it would seem some level of matching the lineup to conventional positions is appropriate. But could you get by with a PG and 4 of the 5 above? Who’s to say which positions are required to be successful. Would a team with the conventional positions beat one ‘going big’ or ‘going small’? Would a player’s Wins Produced remain consistent if he was on a team of all PF’s and C’s? It seems a team consisting of the league leaders in PAWS would beat a team of only those leading in WS. How consistent with the traditional positions would the PAWS team need to be, though?
There is reluctance to accept the fact that PF’s and C’s are more important to a team’s success, and thus the cry of overweighting rebounds (which accounts for their greater Win Scores). Obviously these positions get more rebounds based only on their position on the floor. Does this mean they are more important to their team’s success?
John
July 16, 2007
I think a lot of you are missing the point. The point is not that Rashard Lewis is a “bad” power forward. The point is about rational economic activity. If we consider a team to be a rational economic entity, it should apportion it’s resources (salaries) to maximize it’s production (wins).
The point is ultimately that Rashard Lewis is significantly above average for a small forward, but only average for a power forward. Essentially what he is trying to say is that Orlando would maximize their investment in Rashard Lewis if they would simply pay a league-average salary to a league-average power forward to play alongside him. Is his ability to play league-average power foward useful? Certainly. There will be times when he will be forced to play the position and it’s better to play him there than someone who’s below average, but to count on that as part of your plan is silly. The only reason any of this matters is that the Magic have tied up a significant amount of their resources in Lewis, they cannot afford for him to give them average production, they need for him to give above-average production. The answer to doing so is relatively simple, pay an average player to rebound and hit the occasional shot at the power forward position, and allow Lewis to dominate small forwards.