Win Shares (jkubatko, 2005)
Posted: Fri Apr 22, 2011 3:02 am
Author Message
jkubatko
Joined: 05 Jan 2005
Posts: 506
Location: Columbus, OH
PostPosted: Wed Feb 16, 2005 3:55 pm Post subject: Win Shares Reply with quote
Some of you may have noticed that I changed the player pages on B-R a bit. I added effective field goal percentage, true shooting percentage, usage rate, and Win Shares to the "Advanced" section. Win Shares? Yes, Win Shares. I came up with a (potentially lame) method for calculating Win Shares for basketball players. I posted a description of the Win Shares method on the site. Any feedback you can provide would be appreciated.
_________________
Regards,
Justin Kubatko
Basketball Stats!
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Yyzlin
Joined: 31 Dec 2004
Posts: 23
Location: North Carolina
PostPosted: Wed Feb 16, 2005 10:45 pm Post subject: Reply with quote
This really hampers players on bad teams and favors players on good teams. You have instances where a player has more win shares than an entire team. That isn't very believable.
Back to top
View user's profile Send private message
admin
Site Admin
Joined: 30 Dec 2004
Posts: 678
Location: Seattle
PostPosted: Thu Feb 17, 2005 12:55 am Post subject: Reply with quote
Justin, how would you say this method improves on, say, just looking at Dean's Individual Wins?
Back to top
View user's profile Send private message Send e-mail Visit poster's website AIM Address
Nikos
Joined: 16 Jan 2005
Posts: 339
PostPosted: Thu Feb 17, 2005 2:02 am Post subject: Reply with quote
Yyzlin wrote:
This really hampers players on bad teams and favors players on good teams. You have instances where a player has more win shares than an entire team. That isn't very believable.
Doesn't WIN % do the same to some degree? At least in the sense where bad teams with players who use a lot of possesions at a solid but not great efficiency level get penalized in a sense?
When I use WIN% I try to keep some perspective about Usage Rate of a player, and if I am going to compare players, I try to compare players who play a similiar role for one team that is on the same talent plain as the other. I guess there is no systematic reasoning, but in my head I usually compare players in similiar systems, who use similiar amount of possesions, while also factoring quality of the team, and some of my own subjective analysis of players.
BTW Yyzlin how do you know a player has more WIN SHARES than an entire team?
Justin, is there any chance when you have spare time you could apply your stats on the player profiles onto the teams as well? It would be immesnly helpful when looking at team snapshots of the past. I am confused as to how Yyzlin came to the conclusion that certain players on good teams have more win shares than entire BAD teams?
Thanks and great job adding those stats so far! You are doing an awesome job with your website, and I find myself using it more and more with each update! I use to frequent BR.com all the time, now I pretty much only using B-R.com!
Back to top
View user's profile Send private message
Mike G
Joined: 14 Jan 2005
Posts: 1501
Location: Delphi, Indiana
PostPosted: Thu Feb 17, 2005 7:37 am Post subject: Reply with quote
I, too, was wondering about the differences between PW and WS. And whether WS could be placed on the team page.
How was it you decided to allott 3 WS per team win? Why not 5? or 1?
I hesitate to ask, but: you aren't considering Loss Shares, are you?
I ran a comparison between your example of the 04 Spurs, and what I call, variously mvp points, team credits, etc, as I generate them:
plr WS TC
TD 33 34.0
MG 23 21.8
TP 20 21.9
RN 19 19.8
HT 17 16.8
BB 15 12.7
RH 12 11.0
MR 10 11.4
JH 05 5.0
DB 04 5.3
KW 02 3.8
And so on; it's apparent that subtracting out replacement value strips something away from the bench warmers. And that defensive credit for Ginobili, Bowen, and Horry gives more WS credits than my system does.
As with Player Wins, my heart and mind agree with the premise and the results. I like it.
Back to top
View user's profile Send private message Send e-mail
jkubatko
Joined: 05 Jan 2005
Posts: 506
Location: Columbus, OH
PostPosted: Thu Feb 17, 2005 11:33 am Post subject: Reply with quote
Mike G wrote:
I, too, was wondering about the differences between PW and WS. And whether WS could be placed on the team page.
I'll get to the questions later, but I just wanted to let everybody know that Win Shares are now on the team pages as well.
_________________
Regards,
Justin Kubatko
Basketball Stats!
Last edited by jkubatko on Thu Feb 17, 2005 3:47 pm; edited 1 time in total
Back to top
View user's profile Send private message Send e-mail Visit poster's website
NickS
Joined: 30 Dec 2004
Posts: 241
PostPosted: Thu Feb 17, 2005 12:51 pm Post subject: Reply with quote
Yyzlin wrote:
This really hampers players on bad teams and favors players on good teams.
Given that a 25 year old Reggie Miller on a .500 Pacers team has 4 more win shares than Duncan did last season I'm not sure about that.
I do think it benefits people who are the one star on teams with a variety of average teammates. [checks]
Actually I see that's not the case.
Look at san antonio (http://www.basketball-reference.com/teams/SAS/1996.html) in a year when David Robinson averaged 25,12,3, and 3.
Robinson has twice as many win shares as the next best player on the team but that's on a season where he has almost as many net player wins as the next 4 best players on the team put together.
Looking at a couple of teams/players I have to say that the win shares numbers look reasonable.
Back to top
View user's profile Send private message
Ben
Joined: 13 Jan 2005
Posts: 202
Location: Iowa City
PostPosted: Thu Feb 17, 2005 2:25 pm Post subject: Reply with quote
Mike G wrote:
How was it you decided to allott 3 WS per team win? Why not 5? or 1?
As with Player Wins, my heart and mind agree with the premise and the results. I like it.
He's probably following Bill James. That begs the question, but I think that's what it is. Personally, I'd go with straight wins and include a decimal place. I really like the idea of dividing up team wins and like Justin's results generally, but IMHO, it looks like the importance of scoring efficiency is exaggerated in his results.
Back to top
View user's profile Send private message
Ed Küpfer
Joined: 30 Dec 2004
Posts: 616
Location: Toronto
PostPosted: Thu Feb 17, 2005 2:47 pm Post subject: Reply with quote
Justin, please, please, please lose the 3 WS = 1 win thing. It adds needless complexity for zero gain. A win is a win -- if a win share is not directly analogous to a win, lets call it something else. If it is -- and I think it's supposed to be -- lets make it a win. This is just about the silliest idea Bill James ever came up with -- lets just steal his good ideas, and leave the bad ones alone.
Quote:
Marginal points allowed are 1.08 times expected points allowed minus points allowed.
Where did the 1.08 come from? Did I miss it? Was it derived empirically, or theoretically? Is it similar to the 0.52 multiplier in the baseball win shares calculations, which were derived (IIRC) empirically?
_________________
ed
Back to top
View user's profile Send private message
jkubatko
Joined: 05 Jan 2005
Posts: 506
Location: Columbus, OH
PostPosted: Thu Feb 17, 2005 4:02 pm Post subject: Reply with quote
Ed Küpfer wrote:
Where did the 1.08 come from? Did I miss it? Was it derived empirically, or theoretically? Is it similar to the 0.52 multiplier in the baseball win shares calculations, which were derived (IIRC) empirically?
Good question. I figured a team made up of marginal players would win about 10% of their games. So, I solved the following equation for x:
Code:
(1 - x)^14 / ((1 - x)^14 + (1 + x)^14)) = 0.10
The value of x is roughly 0.08, so 1 - x = 0.92 and 1 + x = 1.08. I then tested this to see if marginal points would do a good job of predicting team wins. The relationship between marginal points and wins was:
Code:
1 win = 33 marginal points => predicted wins = marginal points / 33
The RMSE using this method to predict team wins was 4.2 wins, which I thought was decent.
_________________
Regards,
Justin Kubatko
Basketball Stats!
Back to top
View user's profile Send private message Send e-mail Visit poster's website
jkubatko
Joined: 05 Jan 2005
Posts: 506
Location: Columbus, OH
PostPosted: Thu Feb 17, 2005 4:58 pm Post subject: Reply with quote
Yyzlin wrote:
You have instances where a player has more win shares than an entire team. That isn't very believable.
Why not? The 1993 Dallas Mavericks had just 11 wins, or 33 win shares. Why is it such a stretch to believe that the 1993 Chicago Bulls (57 wins, 171 win shares) had one player (Michale Jordan) with more win shares than the Mavericks? Keep in mind, that doesn't mean that Jordan would have beaten the Mavericks by himself.
_________________
Regards,
Justin Kubatko
Basketball Stats!
Back to top
View user's profile Send private message Send e-mail Visit poster's website
jkubatko
Joined: 05 Jan 2005
Posts: 506
Location: Columbus, OH
PostPosted: Thu Feb 17, 2005 5:30 pm Post subject: Reply with quote
Ed Küpfer wrote:
Justin, please, please, please lose the 3 WS = 1 win thing. It adds needless complexity for zero gain. A win is a win -- if a win share is not directly analogous to a win, lets call it something else. If it is -- and I think it's supposed to be -- lets make it a win. This is just about the silliest idea Bill James ever came up with -- lets just steal his good ideas, and leave the bad ones alone.
You know, I didn't like the 3 WS = 1 win approach when James first preseneted it, but it grew on me. Here are two reasons why I like it:
1) It summarizes the player's season value into an integer. It's easier to remember that a player had 25 win shares as opposed to 8.33 wins
2) It makes it easier to see meaningful differences in players. If Ed has 34 win shares and Justin has 32 win shares, I think in most cases it would be safe to say that Ed had the more vaulable season. The difference of 2 win shares makes that fairly easy to see. But if I said Ed had 11.33 wins and Justin had 10.67 wins, I think it's harder to determine if that difference is meaningful.
You might respond "So what?" to both points above. If you really hate the 3 WS = 1 win approach, there's probably not much I can do to change your mind.
_________________
Regards,
Justin Kubatko
Basketball Stats!
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Yyzlin
Joined: 31 Dec 2004
Posts: 23
Location: North Carolina
PostPosted: Thu Feb 17, 2005 8:40 pm Post subject: Reply with quote
Quote:
Doesn't WIN % do the same to some degree? At least in the sense where bad teams with players who use a lot of possesions at a solid but not great efficiency level get penalized in a sense?
When I use WIN% I try to keep some perspective about Usage Rate of a player, and if I am going to compare players, I try to compare players who play a similiar role for one team that is on the same talent plain as the other. I guess there is no systematic reasoning, but in my head I usually compare players in similiar systems, who use similiar amount of possesions, while also factoring quality of the team, and some of my own subjective analysis of players.
You act as if Win Shares and WIN% are trying to accomplish the same thing, when in actuality, the purposes of both statistics are entirely different.
Quote:
BTW Yyzlin how do you know a player has more WIN SHARES than an entire team?
Just browsing the statistics, you find that league leaders usually end up around 40+ win shares. Thus, any team with 13 or so less wins has less win shares than some individuals.
Back to top
View user's profile Send private message
Yyzlin
Joined: 31 Dec 2004
Posts: 23
Location: North Carolina
PostPosted: Thu Feb 17, 2005 8:45 pm Post subject: Reply with quote
jkubatko wrote:
Yyzlin wrote:
You have instances where a player has more win shares than an entire team. That isn't very believable.
Why not? The 1993 Dallas Mavericks had just 11 wins, or 33 win shares. Why is it such a stretch to believe that the 1993 Chicago Bulls (57 wins, 171 win shares) had one player (Michale Jordan) with more win shares than the Mavericks? Keep in mind, that doesn't mean that Jordan would have beaten the Mavericks by himself.
Michael Jordan, perhaps. But Brad Daugherty, who ended up with 34 WS? No. The point I was trying to make is, they have biases because of the team record. I think Tracy McGrady serves as a good case study here. In 2002-2003, he had 43 WS. In 2003-2004, he had 19 WS. Maybe you do, but I certainly don't think his performance had dropped that much.
Back to top
View user's profile Send private message
Nikos
Joined: 16 Jan 2005
Posts: 339
PostPosted: Thu Feb 17, 2005 9:14 pm Post subject: Reply with quote
I kind of look at them the same. Both kind of give some sort of value to a player.
Theoretically I guess they are different, but I still use them in a similiar context. They are actually quite close if you factor in WIn % and Usage Rate of a player. The best players usually get rewarded in both systems by either having a high # of total wins or high win shares. Of course the team has to WIN to get the benefit of the doubt in the stats as well, but if Tmac can only produce 19 wins, then I guess he should be bashed in the stats. After all, teams with hardly any talent at all have won more games. Just goes to show how Tmac probably dogged way too many games, and put up some empty stats in 0304.
I have to look into Win Shares more, but by looking at different players, I like the way the numbers stack up for some reason.
As an aside, Horace is still better than Scottie when you factor Win Shares. Pippen has more player wins in most seasons, but is less efficient, but uses many more possesions. Unfortnely the Win Shares method doesn't really give Pippen enough credit, but this is a rare example that appears as NOISE. Safe to say that Horace was just an ultra efficient role player, as good as it gets. A true championship role player who just does not makes mistakes and produces on both ends efficiently.
Pippen's intagibles probably do not show as much in the stats, but by 90-91 I would say Pippen was better than Horice. I guess in 89-90 you could make the case Horace was slightly more valuable and efficient without Scotties extra usage rate being a big factor at that point.
jkubatko
Joined: 05 Jan 2005
Posts: 702
Location: Columbus, OH
PostPosted: Thu Feb 17, 2005 11:34 pm Post subject: Reply with quote
Yyzlin wrote:
Michael Jordan, perhaps. But Brad Daugherty, who ended up with 34 WS? No.
Brad Daugherty was very, very good in 1992. The Cavs finished 2nd in the Eastern Conference with 57 wins. Daugherty was the team leader in points per game (by 4.2), rebounds per game (by 2.1), and minutes per game. He shot 57% from the floor (4th in the league) and 77% from the line. His PSA was 1.26 (3rd in the league) and his PER was 23.0 (7th in the league). He averaged 3.6 assists per game. We tend to overlook players such as Daugherty who do not have a signature skill but do many things very well.
_________________
Regards,
Justin Kubatko
Basketball-Reference.com
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Nikos
Joined: 16 Jan 2005
Posts: 346
PostPosted: Thu Feb 17, 2005 11:40 pm Post subject: Reply with quote
Not only was Daughtery good, Nance was highly underatted as well. Price was an elite PG that year, and John Williams was rock solid. Despite having a lot of help, Daughtery was solid himself, and argualy there best player. Price and Nance were basically on the same level, but Daughtery might have been their best player that particular year.
Back to top
View user's profile Send private message
Kevin Pelton
Site Admin
Joined: 30 Dec 2004
Posts: 978
Location: Seattle
PostPosted: Fri Feb 18, 2005 12:09 am Post subject: Reply with quote
It's worth pointing out that Dean Oliver has Daugherty rated as worth 10.9 wins that season, or equivalent to 33 Win Shares. So Justin is certainly not going out on a limb all by himself by rating Daugherty this well.
I have Daugherty rated at 8.9 Net Wins and 13.3 Wins Above Replacement Player. He, Nance and Price all rated with double-digit WARP that season; Chicago was the only other team with three players in double-figures. (And yes, Nikos, I have Pippen rated better than Grant. Wink)
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Nikos
Joined: 16 Jan 2005
Posts: 346
PostPosted: Fri Feb 18, 2005 12:27 am Post subject: Reply with quote
Admin can I see your database somehow? I'm interested to see past stats/rankings and your version of todays NBA rankings.
Thanks
Back to top
View user's profile Send private message
Yyzlin
Joined: 31 Dec 2004
Posts: 27
Location: North Carolina
PostPosted: Fri Feb 18, 2005 1:10 am Post subject: Reply with quote
I realize that Daugherty was stellar that year, but I don't think he would have lead a team filled with 0 WS-type players to 11 wins. If McGrady, who had a career high of 43 WS, could only lead a team with a very poor, but better cast than hypothesized for Daugherty to 19 wins, I have trouble believing Daugherty could do the same.
Also, you have to take a look at the results. Isn't having Stojakovic and Cassell both ranking as a better player than Duncan last year a bit curious?
Back to top
View user's profile Send private message
Nikos
Joined: 16 Jan 2005
Posts: 346
PostPosted: Fri Feb 18, 2005 1:13 am Post subject: Reply with quote
Duncan played 69 games, Cassell and Peja played a full season if I remember correctly?
Back to top
View user's profile Send private message
Kevin Pelton
Site Admin
Joined: 30 Dec 2004
Posts: 978
Location: Seattle
PostPosted: Fri Feb 18, 2005 1:22 am Post subject: Reply with quote
Yyzlin wrote:
If McGrady, who had a career high of 43 WS, could only lead a team with a very poor, but better cast than hypothesized for Daugherty to 19 wins, I have trouble believing Daugherty could do the same.
Depends; would Daugherty decide that playing defense and driving to the basket were beneath him?
Quote:
Also, you have to take a look at the results. Isn't having Stojakovic and Cassell both ranking as a better player than Duncan last year a bit curious?
I don't agree with that result, but it's hardly calling a rookie Andrei Kirilenko the league's second-best player; putting Stojakovic and Cassell over Duncan doesn't not pass my laugh test.
Back to top
View user's profile Send private message Send e-mail Visit poster's website
jkubatko
Joined: 05 Jan 2005
Posts: 702
Location: Columbus, OH
PostPosted: Fri Feb 18, 2005 9:39 am Post subject: Reply with quote
Yyzlin wrote:
Also, you have to take a look at the results. Isn't having Stojakovic and Cassell both ranking as a better player than Duncan last year a bit curious?
You're assuming "more" equals "best". Cassell and Stojakovic both played in 81 games last year, while Duncan played in 69 games. That explains all of the difference between Duncan and Cassell, and most of the difference between Duncan and Stojakovic. You also have to remember that Stojakovic was a phenomenal offensive player in 2004. His effective FG% was 56.6% (that includes 554 three-point attempts) and he shot 92.7% from the line (425 free throw attempts). He managed those numbers while playing slightly over 40 minutes per game (Duncan averaged about 4 minutes per game less). How much a player plays is going to influence how many win shares he earns.
_________________
Regards,
Justin Kubatko
Basketball-Reference.com
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Yyzlin
Joined: 31 Dec 2004
Posts: 27
Location: North Carolina
PostPosted: Fri Feb 18, 2005 10:33 am Post subject: Reply with quote
Quote:
Depends; would Daugherty decide that playing defense and driving to the basket were beneath him?
Depends; do you actually believe that McGrady conciously just decided to stop playing defense and driving to the basket, or perhaps the team context had a large part to do with that? It's not easy when entire defenses are honed on to you without any other significant help. The loss of Garrity was much more detrimental that anticipated. The defense part was just widespread. No one played defense on that team. I'm not sure why, but some of the blame has to go to the coach when defensive rotation was almost non-existant.
Back to top
View user's profile Send private message
Yyzlin
Joined: 31 Dec 2004
Posts: 27
Location: North Carolina
PostPosted: Fri Feb 18, 2005 10:34 am Post subject: Reply with quote
jkubatko wrote:
Yyzlin wrote:
Also, you have to take a look at the results. Isn't having Stojakovic and Cassell both ranking as a better player than Duncan last year a bit curious?
You're assuming "more" equals "best". Cassell and Stojakovic both played in 81 games last year, while Duncan played in 69 games. That explains all of the difference between Duncan and Cassell, and most of the difference between Duncan and Stojakovic. You also have to remember that Stojakovic was a phenomenal offensive player in 2004. His effective FG% was 56.6% (that includes 554 three-point attempts) and he shot 92.7% from the line (425 free throw attempts). He managed those numbers while playing slightly over 40 minutes per game (Duncan averaged about 4 minutes per game less). How much a player plays is going to influence how many win shares he earns.
My bad. The fact that Duncan missed a portion of last season slipped my mind. The results are much more palatable ocne you take that into account.
Back to top
View user's profile Send private message
Kevin Pelton
Site Admin
Joined: 30 Dec 2004
Posts: 978
Location: Seattle
PostPosted: Fri Feb 18, 2005 10:46 am Post subject: Reply with quote
Yyzlin wrote:
Depends; do you actually believe that McGrady conciously just decided to stop playing defense and driving to the basket, or perhaps the team context had a large part to do with that?
But how do you decide (statistically) when a player is really worse and when he's just playing at half-speed because his team is so bad? How do you design a rating system that takes that into account? Is the point of a rating system to evaluate how players did that season, or how they're going to fare going forward?
Back to top
View user's profile Send private message Send e-mail Visit poster's website
jkubatko
Joined: 05 Jan 2005
Posts: 702
Location: Columbus, OH
PostPosted: Fri Feb 18, 2005 11:00 am Post subject: Reply with quote
Yyzlin wrote:
Depends; do you actually believe that McGrady conciously just decided to stop playing defense and driving to the basket, or perhaps the team context had a large part to do with that?
I believe the former, as McGrady so much as admitted in Sports Illustrated about a month ago that he dogged it at times last year.
_________________
Regards,
Justin Kubatko
Basketball-Reference.com
Back to top
View user's profile Send private message Send e-mail Visit poster's website
jkubatko
Joined: 05 Jan 2005
Posts: 702
Location: Columbus, OH
PostPosted: Fri Feb 18, 2005 11:02 am Post subject: Reply with quote
admin wrote:
But how do you decide (statistically) when a player is really worse and when he's just playing at half-speed because his team is so bad? How do you design a rating system that takes that into account? Is the point of a rating system to evaluate how players did that season, or how they're going to fare going forward?
Good points. I view Win Shares as retrospective rather than prospective.
_________________
Regards,
Justin Kubatko
Basketball-Reference.com
Back to top
View user's profile Send private message Send e-mail Visit poster's website
bchaikin
Joined: 27 Jan 2005
Posts: 686
Location: cleveland, ohio
PostPosted: Fri Feb 18, 2005 12:20 pm Post subject: Reply with quote
Brad Daugherty was very, very good in 1992. The Cavs finished 2nd in the Eastern Conference with 57 wins. Daugherty was the team leader in points per game (by 4.2), rebounds per game (by 2.1), and minutes per game. He shot 57% from the floor (4th in the league) and 77% from the line. His PSA was 1.26 (3rd in the league) and his PER was 23.0 (7th in the league). He averaged 3.6 assists per game. We tend to overlook players such as Daugherty who do not have a signature skill but do many things very well.
Not only was Daughtery good, Nance was highly underatted as well. Price was an elite PG that year, and John Williams was rock solid. Despite having a lot of help, Daughtery was solid himself, and argualy there best player. Price and Nance were basically on the same level, but Daughtery might have been their best player that particular year.
in 91-92 brad daugherty had the 2nd best Scoring FG% (combining 2pters, 3pters, and FTs) in the league behind reggie miller. simulation shows he was the 4th best center in the league behind david robinson, hakeem olajuwon, and patrick ewing in terms of producing wins for his team, and just about as good as ewing. his turnovers per touch that season (just 6%) was lower than all three of the centers mentioned above...
most people think the cavs were a premier defensive team that season with larry nance and hotrod williams, but in reality the cavs had just the league's 12th best team defensive points per possession (out of 27 teams). where they excelled however was on offense - that year the cavs had the 2nd best team offensive points per possession behind only the bulls. they were quite an efficient offense and daugherty was the main reason for that...
Depends; would Daugherty decide that playing defense and driving to the basket were beneath him?
daugherty was not a robinson or olajuwon on defense, but he certainly was no slouch (i have him rated as an average defender that season). he was a big body that could move anyone off the blocks and it wasn't often that he was dominated by an opposing center. a cursory glance at the cavs 9192 box scores shows how he held up against the best centers that season (the parenthesis have what daugherty scored, the other what the opposing center scored):
hou - olajuwon 12 (13), 12 (1Cool
san - robinson 31 (26), 14 (31)
nyk - ewing 22 (23), 28 (31), 26 (19), 13 (22)
btw - that 91-92 season had what simulation shows is probably the most prolific season by a single player in terms of generating the most wins for his team over the past 25/27 years - by david robinson of the spurs. playing 40 min/g and 82 games simulation shows he'd get somewhere in the neighborhood of 1000+ rebs, 190+ steals, and 370+ blocks, while scoring 22/23 pts/g with a Scoring FG% of about 58% and just 7% turnovers per touch. i have him rated as an excellent defender that season (he was on the all-D 1st team that year)....
that performance topped even olajuwon's 8990 season which was statistically similar except he shot worse and committed more turnovers per touch than robinson did in 9192...
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Mike G
Joined: 14 Jan 2005
Posts: 3578
Location: Hendersonville, NC
PostPosted: Fri Feb 18, 2005 12:42 pm Post subject: Reply with quote
jkubatko wrote:
Ed Küpfer wrote:
Justin, please, please, please lose the 3 WS = 1 win thing..
Here are two reasons why I like it:
1) It summarizes the player's season value into an integer. It's easier to remember that a player had 25 win shares as opposed to 8.33 wins
2) It makes it easier to see meaningful differences in players. If Ed has 34 win shares and Justin has 32 win shares, I think in most cases it would be safe to say that Ed had the more vaulable season. The difference of 2 win shares makes that fairly easy to see. But if I said Ed had 11.33 wins and Justin had 10.67 wins, I think it's harder to determine if that difference is meaningful.
You might respond "So what?" to both points above. If you really hate the 3 WS = 1 win approach, there's probably not much I can do to change your mind.
I have to agree entirely with Ed. Pretending that your WS are "integers" don't make it so. Why imagine 2 decimal places belong here, and zero there? If 2 players show 8 WS, I have to think "something between 7.5 and 8.5". No one here is fooled.
The formulae you use don't produce integers. You may safely drop that notion.
Most of our stats look good at 3 significant digits: .523 is an appropriate TS%. When you show PSA, it's 1.05. Which tells us more? That's where you have to just find your comfort level.
BTW -- I Love This Game!
Ed Küpfer
Joined: 30 Dec 2004
Posts: 785
Location: Toronto
PostPosted: Fri Feb 18, 2005 1:10 pm Post subject: Reply with quote
jkubatko wrote:
The RMSE using this method to predict team wins was 4.2 wins, which I thought was decent.
Which it is. The RMSE with Pythagoreanish methods is between 3 and 4, so that sounds right.
jkubatko wrote:
You know, I didn't like the 3 WS = 1 win approach when James first preseneted it, but it grew on me. Here are two reasons why I like it:
There's probably no reason to drive this one into the ground, so I'll just drop the whole thing. It's an argument about presentation, basically, not methodology, so it really isn't important in the grand scheme.
_________________
ed
Back to top
View user's profile Send private message Send e-mail
jkubatko
Joined: 05 Jan 2005
Posts: 702
Location: Columbus, OH
PostPosted: Fri Feb 18, 2005 2:33 pm Post subject: Reply with quote
Ed Küpfer wrote:
jkubatko wrote:
The RMSE using this method to predict team wins was 4.2 wins, which I thought was decent.
Which it is. The RMSE with Pythagoreanish methods is between 3 and 4, so that sounds right.
I also verified this empirically by trying values of x from .001 to .100 (incremented by .001). I think the one that produced the smallest RMSE was x = 0.078, but the differences between x = 0.08 and x = 0.078 were miniscule. I also was also happy that this backed up my intuition about a marginal team.
Ed Küpfer wrote:
jkubatko wrote:
You know, I didn't like the 3 WS = 1 win approach when James first preseneted it, but it grew on me. Here are two reasons why I like it:
There's probably no reason to drive this one into the ground, so I'll just drop the whole thing. It's an argument about presentation, basically, not methodology, so it really isn't important in the grand scheme.
Thanks for saving me from posting a similar thing. I would really like feedback on the methodology. Also, thanks for making me explain the 0.92 and 1.08 multipliers. I will add that to the explanation on my web site soon.
_________________
Regards,
Justin Kubatko
Basketball-Reference.com
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Kevin Pelton
Site Admin
Joined: 30 Dec 2004
Posts: 978
Location: Seattle
PostPosted: Fri Feb 18, 2005 4:37 pm Post subject: Reply with quote
Mike G wrote:
If 2 players show 8 WS, I have to think "something between 7.5 and 8.5".
Can you really find a tangible difference between a player with 7.5 and 8.5 win shares? At some level, differences are overwhelmed by the fact that these are merely estimates.
If you're going to create a rating called Win Shares, you are, for better or worth, trading on Bill James' work. That makes it necessary to follow James' conventions, including 3WS = 1 win and integers only.
I find it fairly interesting that the leaders in NBA Win Shares, at a glance, seem to have similar totals to leaders in MLB.
Back to top
View user's profile Send private message Send e-mail Visit poster's website
HoopStudies
Joined: 30 Dec 2004
Posts: 705
Location: Near Philadelphia, PA
PostPosted: Fri Feb 18, 2005 6:56 pm Post subject: Reply with quote
admin wrote:
I find it fairly interesting that the leaders in NBA Win Shares, at a glance, seem to have similar totals to leaders in MLB.
First of all, the method is definitely kinda cool. Another theoretical way to try to put a player's production in terms of something real (even if James did decide to go with win shares, rather than wins). Nice work, JK.
Second, I had noticed with individual win-loss records that they were comparable to what you get in baseball. Not that I'd ever seen such a thing in baseball, but James always talked about the top players in baseball being worth 10+ extra wins, which is about what I see in indiv w-l records. Justin's calcs reproducing baseball winshare numbers isn't a huge surprise.
The fun, though, is in asking why. Baseball has 2x the games. Baseball plays 9 guys on the field, and maybe 12 guys overall in a game with relief pitchers. We play 5 guys on the court and typically 9 guys overall. So that means distributing the credit (zeroth order) among 1.5 to 2x the guys. 2x the games divided by 2x the guys gives you about the same games per guy. 2x the games divided by 1.5x the guys gives you more games on the baseball side, but then you might say that the top guys in baseball don't have the opportunities to influence a game like the top guys in basketball. A big possession user in basketball gets about 1.5x the number of offensive possessions as an average guy and maybe 1.2x the number of defensive possessions (though most big offensive users are low on the defensive side). So 2x the games divided by 1.5x the guys and 1.2-1.5x the opportunities brings it again right back to about equivalent.
Just fun, but I've always found comparative sport stuff interesting... I have to imagine that football players can't be responsible for more than about a win or two in a season. Maybe it's more because a quarterback is involved in about 50% of all offensive plays. So maybe 4 games for a QB, which is a big deal.
_________________
Dean Oliver
Author, Basketball on Paper
The postings are my own & don't necess represent positions, strategies or opinions of employers.
Back to top
View user's profile Send private message Visit poster's website
Yyzlin
Joined: 31 Dec 2004
Posts: 27
Location: North Carolina
PostPosted: Sat Feb 19, 2005 2:08 am Post subject: Reply with quote
admin wrote:
Yyzlin wrote:
Depends; do you actually believe that McGrady conciously just decided to stop playing defense and driving to the basket, or perhaps the team context had a large part to do with that?
But how do you decide (statistically) when a player is really worse and when he's just playing at half-speed because his team is so bad? How do you design a rating system that takes that into account? Is the point of a rating system to evaluate how players did that season, or how they're going to fare going forward?
That's my point though. If McGrady, whose peak was much higher than Daugherty's suffered such a supposed drop-off because of the poor play of his teammates, would it not be assumed than Daugherty might experience similar troubles?
Back to top
View user's profile Send private message
Yyzlin
Joined: 31 Dec 2004
Posts: 27
Location: North Carolina
PostPosted: Sat Feb 19, 2005 2:09 am Post subject: Reply with quote
jkubatko wrote:
Yyzlin wrote:
Depends; do you actually believe that McGrady conciously just decided to stop playing defense and driving to the basket, or perhaps the team context had a large part to do with that?
I believe the former, as McGrady so much as admitted in Sports Illustrated about a month ago that he dogged it at times last year.
So, right at the beginning of the season, McGrady just decided to not go full speed? Please. It was obviously only through a good portion of the season had passed when the team was obviously not going anywhere that McGrady would dog it.
Back to top
View user's profile Send private message
Ed Küpfer
Joined: 30 Dec 2004
Posts: 785
Location: Toronto
PostPosted: Sat Feb 19, 2005 4:37 am Post subject: Reply with quote
Just for fun. I have no comment.
_________________
ed
Back to top
View user's profile Send private message Send e-mail
Ed Küpfer
Joined: 30 Dec 2004
Posts: 785
Location: Toronto
PostPosted: Sat Feb 19, 2005 4:45 am Post subject: Reply with quote
Justin: Any chance you could post a complete season's worth of Win Shares for all players so's I can fiddle? Any season will do.
_________________
ed
Back to top
View user's profile Send private message Send e-mail
Mike G
Joined: 14 Jan 2005
Posts: 3552
Location: Hendersonville, NC
PostPosted: Sat Feb 19, 2005 6:52 am Post subject: Reply with quote
Ed -- the graphs are really cute. The 5-game clustered stats are more, uh, viewable even. What about doing season-cumulative averages, so's we could see how a player's whole year is adding up. For the current season, Vince Carter's move Up has been noted. You could see when Garnett "peaked".
Back to top
View user's profile Send private message Send e-mail
Ed Küpfer
Joined: 30 Dec 2004
Posts: 785
Location: Toronto
PostPosted: Sat Feb 19, 2005 12:11 pm Post subject: Reply with quote
_________________
ed
Back to top
View user's profile Send private message Send e-mail
kjb
Joined: 03 Jan 2005
Posts: 864
Location: Washington, DC
PostPosted: Sat Feb 19, 2005 12:44 pm Post subject: Reply with quote
Eyeballing the cumulative averages graph, it looks like McGrady may have started slacking off defensively in late December.
Back to top
View user's profile Send private message AIM Address Yahoo Messenger
Yyzlin
Joined: 31 Dec 2004
Posts: 27
Location: North Carolina
PostPosted: Sat Feb 19, 2005 1:25 pm Post subject: Reply with quote
Yeah. Very nice graphs. It does appear that McGrady had a noticable drop in defense starting around the end of December.
Back to top
View user's profile Send private message
S.K.
Joined: 18 Feb 2005
Posts: 61
Location: Toronto
PostPosted: Sat Feb 19, 2005 4:25 pm Post subject: Reply with quote
Interesting that his offense traveled upwards from that point at almost the same rate - so not a general malaise, just a concerted avoidance of doing anything he personally wouldn't benefit from (ie stat padding).
_________________
No books - no articles - no website.
Just opinions.
Ill-informed opinions.
Back to top
View user's profile Send private message Send e-mail MSN Messenger
Mike G
Joined: 14 Jan 2005
Posts: 3552
Location: Hendersonville, NC
PostPosted: Mon Feb 21, 2005 11:54 am Post subject: Reply with quote
Having hand-entered every 2004 "win-share" and "player win" number at b-r.com, I went looking for players who have the biggest difference (after multiplying PW by 3). PW favors these players, relative to WS:
D-J PW3 WS player
9.1 29.4 20 Shawn Marion
8.7 30.0 21 Donyell Marshall
7.7 24.0 16 Marcus Camby
7.6 33.9 26 Ben Wallace
6.5 22.8 16 Samuel Dalembert
6.4 23.7 17 Kenyon Martin
6.3 36.6 30 Andrei Kirilenko
6.1 32.4 26 Jermaine O'Neal
5.6 27.9 22 Lamar Odom
5.4 38.7 33 Tim Duncan
All these guys are big rebounders, or they have big defensive numbers (steals, blocks), or both.
Here are players that get more credit in the WS method than in PW:
D-J pw3 ws
-6.9 35.4 42 Predrag Stojakovic
-6.5 28.8 35 Kobe Bryant
-6.4 21.9 28 Reggie Miller
-4.9 23.4 28 Gary Payton
-4.8 25.5 30 Mike Bibby
-4.5 31.8 36 Sam Cassell
-4.5 22.8 27 Steve Nash
-4.3 21.0 25 Jeff Foster
-3.9 14.4 18 Stephon Marbury
-3.7 0.6 4 Milt Palacio
The negative sign just means this is the bottom of the list, inverted. All these guys are high-TS%, high Ast/TO, or named Milt.
I can't seem to come up with an equivalent system that is as close to either of these as they are to one another. And I'm not sure that I want to. But what I've got right now is something I could call "expected win shares with an average team". And this just means there's no a priori bias toward guys on good/bad teams. A great player on a rotten team should produce substantial wins on an average team.
Here are players that look better in my "T2" system than in Justin's WS column:
M-J mT2 WS
14.1 29.1 15 Vince Carter
12.9 20.9 8 Allen Iverson
11.4 26.4 15 Lebron James
11.1 29.1 18 Paul Pierce
10.4 20.4 10 Jamal Crawford
9.9 28.9 19 Tracy Mcgrady
9.2 13.2 4 Drew Gooden
9.0 29.0 20 Zach Randolph
8.7 22.7 14 Jason Richardson
8.2 28.2 20 Baron Davis
As expected, all players from mediocre-to-bad clubs.
Comparing my little list to the PW list:
M-D mgT2 PW
11.9 26.4 14.7 Lebron James
11.4 20.9 9.6 Allen Iverson
11.3 29.1 18.0 Vince Carter
9.1 20.4 11.4 Jamal Crawford
8.9 18.1 9.3 Joe Johnson
8.9 13.2 4.5 Jalen Rose
8.7 28.9 20.4 Tracy Mcgrady
8.3 19.3 11.1 Antoine Walker
8.0 14.8 6.9 Quentin Richardson
7.9 12.9 5.1 Ronald Murray
Again, the PW figure is 3x that shown at b-r.com. Lebron's number is almost identical in the other 2 lists.
Back to top
View user's profile Send private message Send e-mail
Ed Küpfer
Joined: 30 Dec 2004
Posts: 785
Location: Toronto
PostPosted: Thu Feb 24, 2005 2:46 pm Post subject: Reply with quote
For years I've been using a Wins Above Replacement measure that gives out pseudo-Win Shares results. I calculate is like this:
Code:
WAR = Games * (Win% - x)
where Games is Oliverian wins plus losses, Win% is the ratio of wins to Games, and x is a replacement level. I typically set x at 10% or 20%, calling the results WAR10 and WAR20 respectively.
I compared WAR*3 to player WS over the last 5 season, and the results were very close. In the WAR20 sample, 1381 of the 2401 players (58%) came within +/- 3 WS. WAR10 was even better: 1846 players (77%) came within 3 WS. Finally I tried WAR5, using 5% as my replacement level WIN%, and got the best results of all: 2040 players (85%) were within 3 WS. I consider this supprt for the the WS methodology.
_________________
ed
jkubatko
Joined: 05 Jan 2005
Posts: 506
Location: Columbus, OH
PostPosted: Wed Feb 16, 2005 3:55 pm Post subject: Win Shares Reply with quote
Some of you may have noticed that I changed the player pages on B-R a bit. I added effective field goal percentage, true shooting percentage, usage rate, and Win Shares to the "Advanced" section. Win Shares? Yes, Win Shares. I came up with a (potentially lame) method for calculating Win Shares for basketball players. I posted a description of the Win Shares method on the site. Any feedback you can provide would be appreciated.
_________________
Regards,
Justin Kubatko
Basketball Stats!
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Yyzlin
Joined: 31 Dec 2004
Posts: 23
Location: North Carolina
PostPosted: Wed Feb 16, 2005 10:45 pm Post subject: Reply with quote
This really hampers players on bad teams and favors players on good teams. You have instances where a player has more win shares than an entire team. That isn't very believable.
Back to top
View user's profile Send private message
admin
Site Admin
Joined: 30 Dec 2004
Posts: 678
Location: Seattle
PostPosted: Thu Feb 17, 2005 12:55 am Post subject: Reply with quote
Justin, how would you say this method improves on, say, just looking at Dean's Individual Wins?
Back to top
View user's profile Send private message Send e-mail Visit poster's website AIM Address
Nikos
Joined: 16 Jan 2005
Posts: 339
PostPosted: Thu Feb 17, 2005 2:02 am Post subject: Reply with quote
Yyzlin wrote:
This really hampers players on bad teams and favors players on good teams. You have instances where a player has more win shares than an entire team. That isn't very believable.
Doesn't WIN % do the same to some degree? At least in the sense where bad teams with players who use a lot of possesions at a solid but not great efficiency level get penalized in a sense?
When I use WIN% I try to keep some perspective about Usage Rate of a player, and if I am going to compare players, I try to compare players who play a similiar role for one team that is on the same talent plain as the other. I guess there is no systematic reasoning, but in my head I usually compare players in similiar systems, who use similiar amount of possesions, while also factoring quality of the team, and some of my own subjective analysis of players.
BTW Yyzlin how do you know a player has more WIN SHARES than an entire team?
Justin, is there any chance when you have spare time you could apply your stats on the player profiles onto the teams as well? It would be immesnly helpful when looking at team snapshots of the past. I am confused as to how Yyzlin came to the conclusion that certain players on good teams have more win shares than entire BAD teams?
Thanks and great job adding those stats so far! You are doing an awesome job with your website, and I find myself using it more and more with each update! I use to frequent BR.com all the time, now I pretty much only using B-R.com!
Back to top
View user's profile Send private message
Mike G
Joined: 14 Jan 2005
Posts: 1501
Location: Delphi, Indiana
PostPosted: Thu Feb 17, 2005 7:37 am Post subject: Reply with quote
I, too, was wondering about the differences between PW and WS. And whether WS could be placed on the team page.
How was it you decided to allott 3 WS per team win? Why not 5? or 1?
I hesitate to ask, but: you aren't considering Loss Shares, are you?
I ran a comparison between your example of the 04 Spurs, and what I call, variously mvp points, team credits, etc, as I generate them:
plr WS TC
TD 33 34.0
MG 23 21.8
TP 20 21.9
RN 19 19.8
HT 17 16.8
BB 15 12.7
RH 12 11.0
MR 10 11.4
JH 05 5.0
DB 04 5.3
KW 02 3.8
And so on; it's apparent that subtracting out replacement value strips something away from the bench warmers. And that defensive credit for Ginobili, Bowen, and Horry gives more WS credits than my system does.
As with Player Wins, my heart and mind agree with the premise and the results. I like it.
Back to top
View user's profile Send private message Send e-mail
jkubatko
Joined: 05 Jan 2005
Posts: 506
Location: Columbus, OH
PostPosted: Thu Feb 17, 2005 11:33 am Post subject: Reply with quote
Mike G wrote:
I, too, was wondering about the differences between PW and WS. And whether WS could be placed on the team page.
I'll get to the questions later, but I just wanted to let everybody know that Win Shares are now on the team pages as well.
_________________
Regards,
Justin Kubatko
Basketball Stats!
Last edited by jkubatko on Thu Feb 17, 2005 3:47 pm; edited 1 time in total
Back to top
View user's profile Send private message Send e-mail Visit poster's website
NickS
Joined: 30 Dec 2004
Posts: 241
PostPosted: Thu Feb 17, 2005 12:51 pm Post subject: Reply with quote
Yyzlin wrote:
This really hampers players on bad teams and favors players on good teams.
Given that a 25 year old Reggie Miller on a .500 Pacers team has 4 more win shares than Duncan did last season I'm not sure about that.
I do think it benefits people who are the one star on teams with a variety of average teammates. [checks]
Actually I see that's not the case.
Look at san antonio (http://www.basketball-reference.com/teams/SAS/1996.html) in a year when David Robinson averaged 25,12,3, and 3.
Robinson has twice as many win shares as the next best player on the team but that's on a season where he has almost as many net player wins as the next 4 best players on the team put together.
Looking at a couple of teams/players I have to say that the win shares numbers look reasonable.
Back to top
View user's profile Send private message
Ben
Joined: 13 Jan 2005
Posts: 202
Location: Iowa City
PostPosted: Thu Feb 17, 2005 2:25 pm Post subject: Reply with quote
Mike G wrote:
How was it you decided to allott 3 WS per team win? Why not 5? or 1?
As with Player Wins, my heart and mind agree with the premise and the results. I like it.
He's probably following Bill James. That begs the question, but I think that's what it is. Personally, I'd go with straight wins and include a decimal place. I really like the idea of dividing up team wins and like Justin's results generally, but IMHO, it looks like the importance of scoring efficiency is exaggerated in his results.
Back to top
View user's profile Send private message
Ed Küpfer
Joined: 30 Dec 2004
Posts: 616
Location: Toronto
PostPosted: Thu Feb 17, 2005 2:47 pm Post subject: Reply with quote
Justin, please, please, please lose the 3 WS = 1 win thing. It adds needless complexity for zero gain. A win is a win -- if a win share is not directly analogous to a win, lets call it something else. If it is -- and I think it's supposed to be -- lets make it a win. This is just about the silliest idea Bill James ever came up with -- lets just steal his good ideas, and leave the bad ones alone.
Quote:
Marginal points allowed are 1.08 times expected points allowed minus points allowed.
Where did the 1.08 come from? Did I miss it? Was it derived empirically, or theoretically? Is it similar to the 0.52 multiplier in the baseball win shares calculations, which were derived (IIRC) empirically?
_________________
ed
Back to top
View user's profile Send private message
jkubatko
Joined: 05 Jan 2005
Posts: 506
Location: Columbus, OH
PostPosted: Thu Feb 17, 2005 4:02 pm Post subject: Reply with quote
Ed Küpfer wrote:
Where did the 1.08 come from? Did I miss it? Was it derived empirically, or theoretically? Is it similar to the 0.52 multiplier in the baseball win shares calculations, which were derived (IIRC) empirically?
Good question. I figured a team made up of marginal players would win about 10% of their games. So, I solved the following equation for x:
Code:
(1 - x)^14 / ((1 - x)^14 + (1 + x)^14)) = 0.10
The value of x is roughly 0.08, so 1 - x = 0.92 and 1 + x = 1.08. I then tested this to see if marginal points would do a good job of predicting team wins. The relationship between marginal points and wins was:
Code:
1 win = 33 marginal points => predicted wins = marginal points / 33
The RMSE using this method to predict team wins was 4.2 wins, which I thought was decent.
_________________
Regards,
Justin Kubatko
Basketball Stats!
Back to top
View user's profile Send private message Send e-mail Visit poster's website
jkubatko
Joined: 05 Jan 2005
Posts: 506
Location: Columbus, OH
PostPosted: Thu Feb 17, 2005 4:58 pm Post subject: Reply with quote
Yyzlin wrote:
You have instances where a player has more win shares than an entire team. That isn't very believable.
Why not? The 1993 Dallas Mavericks had just 11 wins, or 33 win shares. Why is it such a stretch to believe that the 1993 Chicago Bulls (57 wins, 171 win shares) had one player (Michale Jordan) with more win shares than the Mavericks? Keep in mind, that doesn't mean that Jordan would have beaten the Mavericks by himself.
_________________
Regards,
Justin Kubatko
Basketball Stats!
Back to top
View user's profile Send private message Send e-mail Visit poster's website
jkubatko
Joined: 05 Jan 2005
Posts: 506
Location: Columbus, OH
PostPosted: Thu Feb 17, 2005 5:30 pm Post subject: Reply with quote
Ed Küpfer wrote:
Justin, please, please, please lose the 3 WS = 1 win thing. It adds needless complexity for zero gain. A win is a win -- if a win share is not directly analogous to a win, lets call it something else. If it is -- and I think it's supposed to be -- lets make it a win. This is just about the silliest idea Bill James ever came up with -- lets just steal his good ideas, and leave the bad ones alone.
You know, I didn't like the 3 WS = 1 win approach when James first preseneted it, but it grew on me. Here are two reasons why I like it:
1) It summarizes the player's season value into an integer. It's easier to remember that a player had 25 win shares as opposed to 8.33 wins
2) It makes it easier to see meaningful differences in players. If Ed has 34 win shares and Justin has 32 win shares, I think in most cases it would be safe to say that Ed had the more vaulable season. The difference of 2 win shares makes that fairly easy to see. But if I said Ed had 11.33 wins and Justin had 10.67 wins, I think it's harder to determine if that difference is meaningful.
You might respond "So what?" to both points above. If you really hate the 3 WS = 1 win approach, there's probably not much I can do to change your mind.
_________________
Regards,
Justin Kubatko
Basketball Stats!
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Yyzlin
Joined: 31 Dec 2004
Posts: 23
Location: North Carolina
PostPosted: Thu Feb 17, 2005 8:40 pm Post subject: Reply with quote
Quote:
Doesn't WIN % do the same to some degree? At least in the sense where bad teams with players who use a lot of possesions at a solid but not great efficiency level get penalized in a sense?
When I use WIN% I try to keep some perspective about Usage Rate of a player, and if I am going to compare players, I try to compare players who play a similiar role for one team that is on the same talent plain as the other. I guess there is no systematic reasoning, but in my head I usually compare players in similiar systems, who use similiar amount of possesions, while also factoring quality of the team, and some of my own subjective analysis of players.
You act as if Win Shares and WIN% are trying to accomplish the same thing, when in actuality, the purposes of both statistics are entirely different.
Quote:
BTW Yyzlin how do you know a player has more WIN SHARES than an entire team?
Just browsing the statistics, you find that league leaders usually end up around 40+ win shares. Thus, any team with 13 or so less wins has less win shares than some individuals.
Back to top
View user's profile Send private message
Yyzlin
Joined: 31 Dec 2004
Posts: 23
Location: North Carolina
PostPosted: Thu Feb 17, 2005 8:45 pm Post subject: Reply with quote
jkubatko wrote:
Yyzlin wrote:
You have instances where a player has more win shares than an entire team. That isn't very believable.
Why not? The 1993 Dallas Mavericks had just 11 wins, or 33 win shares. Why is it such a stretch to believe that the 1993 Chicago Bulls (57 wins, 171 win shares) had one player (Michale Jordan) with more win shares than the Mavericks? Keep in mind, that doesn't mean that Jordan would have beaten the Mavericks by himself.
Michael Jordan, perhaps. But Brad Daugherty, who ended up with 34 WS? No. The point I was trying to make is, they have biases because of the team record. I think Tracy McGrady serves as a good case study here. In 2002-2003, he had 43 WS. In 2003-2004, he had 19 WS. Maybe you do, but I certainly don't think his performance had dropped that much.
Back to top
View user's profile Send private message
Nikos
Joined: 16 Jan 2005
Posts: 339
PostPosted: Thu Feb 17, 2005 9:14 pm Post subject: Reply with quote
I kind of look at them the same. Both kind of give some sort of value to a player.
Theoretically I guess they are different, but I still use them in a similiar context. They are actually quite close if you factor in WIn % and Usage Rate of a player. The best players usually get rewarded in both systems by either having a high # of total wins or high win shares. Of course the team has to WIN to get the benefit of the doubt in the stats as well, but if Tmac can only produce 19 wins, then I guess he should be bashed in the stats. After all, teams with hardly any talent at all have won more games. Just goes to show how Tmac probably dogged way too many games, and put up some empty stats in 0304.
I have to look into Win Shares more, but by looking at different players, I like the way the numbers stack up for some reason.
As an aside, Horace is still better than Scottie when you factor Win Shares. Pippen has more player wins in most seasons, but is less efficient, but uses many more possesions. Unfortnely the Win Shares method doesn't really give Pippen enough credit, but this is a rare example that appears as NOISE. Safe to say that Horace was just an ultra efficient role player, as good as it gets. A true championship role player who just does not makes mistakes and produces on both ends efficiently.
Pippen's intagibles probably do not show as much in the stats, but by 90-91 I would say Pippen was better than Horice. I guess in 89-90 you could make the case Horace was slightly more valuable and efficient without Scotties extra usage rate being a big factor at that point.
jkubatko
Joined: 05 Jan 2005
Posts: 702
Location: Columbus, OH
PostPosted: Thu Feb 17, 2005 11:34 pm Post subject: Reply with quote
Yyzlin wrote:
Michael Jordan, perhaps. But Brad Daugherty, who ended up with 34 WS? No.
Brad Daugherty was very, very good in 1992. The Cavs finished 2nd in the Eastern Conference with 57 wins. Daugherty was the team leader in points per game (by 4.2), rebounds per game (by 2.1), and minutes per game. He shot 57% from the floor (4th in the league) and 77% from the line. His PSA was 1.26 (3rd in the league) and his PER was 23.0 (7th in the league). He averaged 3.6 assists per game. We tend to overlook players such as Daugherty who do not have a signature skill but do many things very well.
_________________
Regards,
Justin Kubatko
Basketball-Reference.com
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Nikos
Joined: 16 Jan 2005
Posts: 346
PostPosted: Thu Feb 17, 2005 11:40 pm Post subject: Reply with quote
Not only was Daughtery good, Nance was highly underatted as well. Price was an elite PG that year, and John Williams was rock solid. Despite having a lot of help, Daughtery was solid himself, and argualy there best player. Price and Nance were basically on the same level, but Daughtery might have been their best player that particular year.
Back to top
View user's profile Send private message
Kevin Pelton
Site Admin
Joined: 30 Dec 2004
Posts: 978
Location: Seattle
PostPosted: Fri Feb 18, 2005 12:09 am Post subject: Reply with quote
It's worth pointing out that Dean Oliver has Daugherty rated as worth 10.9 wins that season, or equivalent to 33 Win Shares. So Justin is certainly not going out on a limb all by himself by rating Daugherty this well.
I have Daugherty rated at 8.9 Net Wins and 13.3 Wins Above Replacement Player. He, Nance and Price all rated with double-digit WARP that season; Chicago was the only other team with three players in double-figures. (And yes, Nikos, I have Pippen rated better than Grant. Wink)
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Nikos
Joined: 16 Jan 2005
Posts: 346
PostPosted: Fri Feb 18, 2005 12:27 am Post subject: Reply with quote
Admin can I see your database somehow? I'm interested to see past stats/rankings and your version of todays NBA rankings.
Thanks
Back to top
View user's profile Send private message
Yyzlin
Joined: 31 Dec 2004
Posts: 27
Location: North Carolina
PostPosted: Fri Feb 18, 2005 1:10 am Post subject: Reply with quote
I realize that Daugherty was stellar that year, but I don't think he would have lead a team filled with 0 WS-type players to 11 wins. If McGrady, who had a career high of 43 WS, could only lead a team with a very poor, but better cast than hypothesized for Daugherty to 19 wins, I have trouble believing Daugherty could do the same.
Also, you have to take a look at the results. Isn't having Stojakovic and Cassell both ranking as a better player than Duncan last year a bit curious?
Back to top
View user's profile Send private message
Nikos
Joined: 16 Jan 2005
Posts: 346
PostPosted: Fri Feb 18, 2005 1:13 am Post subject: Reply with quote
Duncan played 69 games, Cassell and Peja played a full season if I remember correctly?
Back to top
View user's profile Send private message
Kevin Pelton
Site Admin
Joined: 30 Dec 2004
Posts: 978
Location: Seattle
PostPosted: Fri Feb 18, 2005 1:22 am Post subject: Reply with quote
Yyzlin wrote:
If McGrady, who had a career high of 43 WS, could only lead a team with a very poor, but better cast than hypothesized for Daugherty to 19 wins, I have trouble believing Daugherty could do the same.
Depends; would Daugherty decide that playing defense and driving to the basket were beneath him?
Quote:
Also, you have to take a look at the results. Isn't having Stojakovic and Cassell both ranking as a better player than Duncan last year a bit curious?
I don't agree with that result, but it's hardly calling a rookie Andrei Kirilenko the league's second-best player; putting Stojakovic and Cassell over Duncan doesn't not pass my laugh test.
Back to top
View user's profile Send private message Send e-mail Visit poster's website
jkubatko
Joined: 05 Jan 2005
Posts: 702
Location: Columbus, OH
PostPosted: Fri Feb 18, 2005 9:39 am Post subject: Reply with quote
Yyzlin wrote:
Also, you have to take a look at the results. Isn't having Stojakovic and Cassell both ranking as a better player than Duncan last year a bit curious?
You're assuming "more" equals "best". Cassell and Stojakovic both played in 81 games last year, while Duncan played in 69 games. That explains all of the difference between Duncan and Cassell, and most of the difference between Duncan and Stojakovic. You also have to remember that Stojakovic was a phenomenal offensive player in 2004. His effective FG% was 56.6% (that includes 554 three-point attempts) and he shot 92.7% from the line (425 free throw attempts). He managed those numbers while playing slightly over 40 minutes per game (Duncan averaged about 4 minutes per game less). How much a player plays is going to influence how many win shares he earns.
_________________
Regards,
Justin Kubatko
Basketball-Reference.com
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Yyzlin
Joined: 31 Dec 2004
Posts: 27
Location: North Carolina
PostPosted: Fri Feb 18, 2005 10:33 am Post subject: Reply with quote
Quote:
Depends; would Daugherty decide that playing defense and driving to the basket were beneath him?
Depends; do you actually believe that McGrady conciously just decided to stop playing defense and driving to the basket, or perhaps the team context had a large part to do with that? It's not easy when entire defenses are honed on to you without any other significant help. The loss of Garrity was much more detrimental that anticipated. The defense part was just widespread. No one played defense on that team. I'm not sure why, but some of the blame has to go to the coach when defensive rotation was almost non-existant.
Back to top
View user's profile Send private message
Yyzlin
Joined: 31 Dec 2004
Posts: 27
Location: North Carolina
PostPosted: Fri Feb 18, 2005 10:34 am Post subject: Reply with quote
jkubatko wrote:
Yyzlin wrote:
Also, you have to take a look at the results. Isn't having Stojakovic and Cassell both ranking as a better player than Duncan last year a bit curious?
You're assuming "more" equals "best". Cassell and Stojakovic both played in 81 games last year, while Duncan played in 69 games. That explains all of the difference between Duncan and Cassell, and most of the difference between Duncan and Stojakovic. You also have to remember that Stojakovic was a phenomenal offensive player in 2004. His effective FG% was 56.6% (that includes 554 three-point attempts) and he shot 92.7% from the line (425 free throw attempts). He managed those numbers while playing slightly over 40 minutes per game (Duncan averaged about 4 minutes per game less). How much a player plays is going to influence how many win shares he earns.
My bad. The fact that Duncan missed a portion of last season slipped my mind. The results are much more palatable ocne you take that into account.
Back to top
View user's profile Send private message
Kevin Pelton
Site Admin
Joined: 30 Dec 2004
Posts: 978
Location: Seattle
PostPosted: Fri Feb 18, 2005 10:46 am Post subject: Reply with quote
Yyzlin wrote:
Depends; do you actually believe that McGrady conciously just decided to stop playing defense and driving to the basket, or perhaps the team context had a large part to do with that?
But how do you decide (statistically) when a player is really worse and when he's just playing at half-speed because his team is so bad? How do you design a rating system that takes that into account? Is the point of a rating system to evaluate how players did that season, or how they're going to fare going forward?
Back to top
View user's profile Send private message Send e-mail Visit poster's website
jkubatko
Joined: 05 Jan 2005
Posts: 702
Location: Columbus, OH
PostPosted: Fri Feb 18, 2005 11:00 am Post subject: Reply with quote
Yyzlin wrote:
Depends; do you actually believe that McGrady conciously just decided to stop playing defense and driving to the basket, or perhaps the team context had a large part to do with that?
I believe the former, as McGrady so much as admitted in Sports Illustrated about a month ago that he dogged it at times last year.
_________________
Regards,
Justin Kubatko
Basketball-Reference.com
Back to top
View user's profile Send private message Send e-mail Visit poster's website
jkubatko
Joined: 05 Jan 2005
Posts: 702
Location: Columbus, OH
PostPosted: Fri Feb 18, 2005 11:02 am Post subject: Reply with quote
admin wrote:
But how do you decide (statistically) when a player is really worse and when he's just playing at half-speed because his team is so bad? How do you design a rating system that takes that into account? Is the point of a rating system to evaluate how players did that season, or how they're going to fare going forward?
Good points. I view Win Shares as retrospective rather than prospective.
_________________
Regards,
Justin Kubatko
Basketball-Reference.com
Back to top
View user's profile Send private message Send e-mail Visit poster's website
bchaikin
Joined: 27 Jan 2005
Posts: 686
Location: cleveland, ohio
PostPosted: Fri Feb 18, 2005 12:20 pm Post subject: Reply with quote
Brad Daugherty was very, very good in 1992. The Cavs finished 2nd in the Eastern Conference with 57 wins. Daugherty was the team leader in points per game (by 4.2), rebounds per game (by 2.1), and minutes per game. He shot 57% from the floor (4th in the league) and 77% from the line. His PSA was 1.26 (3rd in the league) and his PER was 23.0 (7th in the league). He averaged 3.6 assists per game. We tend to overlook players such as Daugherty who do not have a signature skill but do many things very well.
Not only was Daughtery good, Nance was highly underatted as well. Price was an elite PG that year, and John Williams was rock solid. Despite having a lot of help, Daughtery was solid himself, and argualy there best player. Price and Nance were basically on the same level, but Daughtery might have been their best player that particular year.
in 91-92 brad daugherty had the 2nd best Scoring FG% (combining 2pters, 3pters, and FTs) in the league behind reggie miller. simulation shows he was the 4th best center in the league behind david robinson, hakeem olajuwon, and patrick ewing in terms of producing wins for his team, and just about as good as ewing. his turnovers per touch that season (just 6%) was lower than all three of the centers mentioned above...
most people think the cavs were a premier defensive team that season with larry nance and hotrod williams, but in reality the cavs had just the league's 12th best team defensive points per possession (out of 27 teams). where they excelled however was on offense - that year the cavs had the 2nd best team offensive points per possession behind only the bulls. they were quite an efficient offense and daugherty was the main reason for that...
Depends; would Daugherty decide that playing defense and driving to the basket were beneath him?
daugherty was not a robinson or olajuwon on defense, but he certainly was no slouch (i have him rated as an average defender that season). he was a big body that could move anyone off the blocks and it wasn't often that he was dominated by an opposing center. a cursory glance at the cavs 9192 box scores shows how he held up against the best centers that season (the parenthesis have what daugherty scored, the other what the opposing center scored):
hou - olajuwon 12 (13), 12 (1Cool
san - robinson 31 (26), 14 (31)
nyk - ewing 22 (23), 28 (31), 26 (19), 13 (22)
btw - that 91-92 season had what simulation shows is probably the most prolific season by a single player in terms of generating the most wins for his team over the past 25/27 years - by david robinson of the spurs. playing 40 min/g and 82 games simulation shows he'd get somewhere in the neighborhood of 1000+ rebs, 190+ steals, and 370+ blocks, while scoring 22/23 pts/g with a Scoring FG% of about 58% and just 7% turnovers per touch. i have him rated as an excellent defender that season (he was on the all-D 1st team that year)....
that performance topped even olajuwon's 8990 season which was statistically similar except he shot worse and committed more turnovers per touch than robinson did in 9192...
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Mike G
Joined: 14 Jan 2005
Posts: 3578
Location: Hendersonville, NC
PostPosted: Fri Feb 18, 2005 12:42 pm Post subject: Reply with quote
jkubatko wrote:
Ed Küpfer wrote:
Justin, please, please, please lose the 3 WS = 1 win thing..
Here are two reasons why I like it:
1) It summarizes the player's season value into an integer. It's easier to remember that a player had 25 win shares as opposed to 8.33 wins
2) It makes it easier to see meaningful differences in players. If Ed has 34 win shares and Justin has 32 win shares, I think in most cases it would be safe to say that Ed had the more vaulable season. The difference of 2 win shares makes that fairly easy to see. But if I said Ed had 11.33 wins and Justin had 10.67 wins, I think it's harder to determine if that difference is meaningful.
You might respond "So what?" to both points above. If you really hate the 3 WS = 1 win approach, there's probably not much I can do to change your mind.
I have to agree entirely with Ed. Pretending that your WS are "integers" don't make it so. Why imagine 2 decimal places belong here, and zero there? If 2 players show 8 WS, I have to think "something between 7.5 and 8.5". No one here is fooled.
The formulae you use don't produce integers. You may safely drop that notion.
Most of our stats look good at 3 significant digits: .523 is an appropriate TS%. When you show PSA, it's 1.05. Which tells us more? That's where you have to just find your comfort level.
BTW -- I Love This Game!
Ed Küpfer
Joined: 30 Dec 2004
Posts: 785
Location: Toronto
PostPosted: Fri Feb 18, 2005 1:10 pm Post subject: Reply with quote
jkubatko wrote:
The RMSE using this method to predict team wins was 4.2 wins, which I thought was decent.
Which it is. The RMSE with Pythagoreanish methods is between 3 and 4, so that sounds right.
jkubatko wrote:
You know, I didn't like the 3 WS = 1 win approach when James first preseneted it, but it grew on me. Here are two reasons why I like it:
There's probably no reason to drive this one into the ground, so I'll just drop the whole thing. It's an argument about presentation, basically, not methodology, so it really isn't important in the grand scheme.
_________________
ed
Back to top
View user's profile Send private message Send e-mail
jkubatko
Joined: 05 Jan 2005
Posts: 702
Location: Columbus, OH
PostPosted: Fri Feb 18, 2005 2:33 pm Post subject: Reply with quote
Ed Küpfer wrote:
jkubatko wrote:
The RMSE using this method to predict team wins was 4.2 wins, which I thought was decent.
Which it is. The RMSE with Pythagoreanish methods is between 3 and 4, so that sounds right.
I also verified this empirically by trying values of x from .001 to .100 (incremented by .001). I think the one that produced the smallest RMSE was x = 0.078, but the differences between x = 0.08 and x = 0.078 were miniscule. I also was also happy that this backed up my intuition about a marginal team.
Ed Küpfer wrote:
jkubatko wrote:
You know, I didn't like the 3 WS = 1 win approach when James first preseneted it, but it grew on me. Here are two reasons why I like it:
There's probably no reason to drive this one into the ground, so I'll just drop the whole thing. It's an argument about presentation, basically, not methodology, so it really isn't important in the grand scheme.
Thanks for saving me from posting a similar thing. I would really like feedback on the methodology. Also, thanks for making me explain the 0.92 and 1.08 multipliers. I will add that to the explanation on my web site soon.
_________________
Regards,
Justin Kubatko
Basketball-Reference.com
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Kevin Pelton
Site Admin
Joined: 30 Dec 2004
Posts: 978
Location: Seattle
PostPosted: Fri Feb 18, 2005 4:37 pm Post subject: Reply with quote
Mike G wrote:
If 2 players show 8 WS, I have to think "something between 7.5 and 8.5".
Can you really find a tangible difference between a player with 7.5 and 8.5 win shares? At some level, differences are overwhelmed by the fact that these are merely estimates.
If you're going to create a rating called Win Shares, you are, for better or worth, trading on Bill James' work. That makes it necessary to follow James' conventions, including 3WS = 1 win and integers only.
I find it fairly interesting that the leaders in NBA Win Shares, at a glance, seem to have similar totals to leaders in MLB.
Back to top
View user's profile Send private message Send e-mail Visit poster's website
HoopStudies
Joined: 30 Dec 2004
Posts: 705
Location: Near Philadelphia, PA
PostPosted: Fri Feb 18, 2005 6:56 pm Post subject: Reply with quote
admin wrote:
I find it fairly interesting that the leaders in NBA Win Shares, at a glance, seem to have similar totals to leaders in MLB.
First of all, the method is definitely kinda cool. Another theoretical way to try to put a player's production in terms of something real (even if James did decide to go with win shares, rather than wins). Nice work, JK.
Second, I had noticed with individual win-loss records that they were comparable to what you get in baseball. Not that I'd ever seen such a thing in baseball, but James always talked about the top players in baseball being worth 10+ extra wins, which is about what I see in indiv w-l records. Justin's calcs reproducing baseball winshare numbers isn't a huge surprise.
The fun, though, is in asking why. Baseball has 2x the games. Baseball plays 9 guys on the field, and maybe 12 guys overall in a game with relief pitchers. We play 5 guys on the court and typically 9 guys overall. So that means distributing the credit (zeroth order) among 1.5 to 2x the guys. 2x the games divided by 2x the guys gives you about the same games per guy. 2x the games divided by 1.5x the guys gives you more games on the baseball side, but then you might say that the top guys in baseball don't have the opportunities to influence a game like the top guys in basketball. A big possession user in basketball gets about 1.5x the number of offensive possessions as an average guy and maybe 1.2x the number of defensive possessions (though most big offensive users are low on the defensive side). So 2x the games divided by 1.5x the guys and 1.2-1.5x the opportunities brings it again right back to about equivalent.
Just fun, but I've always found comparative sport stuff interesting... I have to imagine that football players can't be responsible for more than about a win or two in a season. Maybe it's more because a quarterback is involved in about 50% of all offensive plays. So maybe 4 games for a QB, which is a big deal.
_________________
Dean Oliver
Author, Basketball on Paper
The postings are my own & don't necess represent positions, strategies or opinions of employers.
Back to top
View user's profile Send private message Visit poster's website
Yyzlin
Joined: 31 Dec 2004
Posts: 27
Location: North Carolina
PostPosted: Sat Feb 19, 2005 2:08 am Post subject: Reply with quote
admin wrote:
Yyzlin wrote:
Depends; do you actually believe that McGrady conciously just decided to stop playing defense and driving to the basket, or perhaps the team context had a large part to do with that?
But how do you decide (statistically) when a player is really worse and when he's just playing at half-speed because his team is so bad? How do you design a rating system that takes that into account? Is the point of a rating system to evaluate how players did that season, or how they're going to fare going forward?
That's my point though. If McGrady, whose peak was much higher than Daugherty's suffered such a supposed drop-off because of the poor play of his teammates, would it not be assumed than Daugherty might experience similar troubles?
Back to top
View user's profile Send private message
Yyzlin
Joined: 31 Dec 2004
Posts: 27
Location: North Carolina
PostPosted: Sat Feb 19, 2005 2:09 am Post subject: Reply with quote
jkubatko wrote:
Yyzlin wrote:
Depends; do you actually believe that McGrady conciously just decided to stop playing defense and driving to the basket, or perhaps the team context had a large part to do with that?
I believe the former, as McGrady so much as admitted in Sports Illustrated about a month ago that he dogged it at times last year.
So, right at the beginning of the season, McGrady just decided to not go full speed? Please. It was obviously only through a good portion of the season had passed when the team was obviously not going anywhere that McGrady would dog it.
Back to top
View user's profile Send private message
Ed Küpfer
Joined: 30 Dec 2004
Posts: 785
Location: Toronto
PostPosted: Sat Feb 19, 2005 4:37 am Post subject: Reply with quote
Just for fun. I have no comment.
_________________
ed
Back to top
View user's profile Send private message Send e-mail
Ed Küpfer
Joined: 30 Dec 2004
Posts: 785
Location: Toronto
PostPosted: Sat Feb 19, 2005 4:45 am Post subject: Reply with quote
Justin: Any chance you could post a complete season's worth of Win Shares for all players so's I can fiddle? Any season will do.
_________________
ed
Back to top
View user's profile Send private message Send e-mail
Mike G
Joined: 14 Jan 2005
Posts: 3552
Location: Hendersonville, NC
PostPosted: Sat Feb 19, 2005 6:52 am Post subject: Reply with quote
Ed -- the graphs are really cute. The 5-game clustered stats are more, uh, viewable even. What about doing season-cumulative averages, so's we could see how a player's whole year is adding up. For the current season, Vince Carter's move Up has been noted. You could see when Garnett "peaked".
Back to top
View user's profile Send private message Send e-mail
Ed Küpfer
Joined: 30 Dec 2004
Posts: 785
Location: Toronto
PostPosted: Sat Feb 19, 2005 12:11 pm Post subject: Reply with quote
_________________
ed
Back to top
View user's profile Send private message Send e-mail
kjb
Joined: 03 Jan 2005
Posts: 864
Location: Washington, DC
PostPosted: Sat Feb 19, 2005 12:44 pm Post subject: Reply with quote
Eyeballing the cumulative averages graph, it looks like McGrady may have started slacking off defensively in late December.
Back to top
View user's profile Send private message AIM Address Yahoo Messenger
Yyzlin
Joined: 31 Dec 2004
Posts: 27
Location: North Carolina
PostPosted: Sat Feb 19, 2005 1:25 pm Post subject: Reply with quote
Yeah. Very nice graphs. It does appear that McGrady had a noticable drop in defense starting around the end of December.
Back to top
View user's profile Send private message
S.K.
Joined: 18 Feb 2005
Posts: 61
Location: Toronto
PostPosted: Sat Feb 19, 2005 4:25 pm Post subject: Reply with quote
Interesting that his offense traveled upwards from that point at almost the same rate - so not a general malaise, just a concerted avoidance of doing anything he personally wouldn't benefit from (ie stat padding).
_________________
No books - no articles - no website.
Just opinions.
Ill-informed opinions.
Back to top
View user's profile Send private message Send e-mail MSN Messenger
Mike G
Joined: 14 Jan 2005
Posts: 3552
Location: Hendersonville, NC
PostPosted: Mon Feb 21, 2005 11:54 am Post subject: Reply with quote
Having hand-entered every 2004 "win-share" and "player win" number at b-r.com, I went looking for players who have the biggest difference (after multiplying PW by 3). PW favors these players, relative to WS:
D-J PW3 WS player
9.1 29.4 20 Shawn Marion
8.7 30.0 21 Donyell Marshall
7.7 24.0 16 Marcus Camby
7.6 33.9 26 Ben Wallace
6.5 22.8 16 Samuel Dalembert
6.4 23.7 17 Kenyon Martin
6.3 36.6 30 Andrei Kirilenko
6.1 32.4 26 Jermaine O'Neal
5.6 27.9 22 Lamar Odom
5.4 38.7 33 Tim Duncan
All these guys are big rebounders, or they have big defensive numbers (steals, blocks), or both.
Here are players that get more credit in the WS method than in PW:
D-J pw3 ws
-6.9 35.4 42 Predrag Stojakovic
-6.5 28.8 35 Kobe Bryant
-6.4 21.9 28 Reggie Miller
-4.9 23.4 28 Gary Payton
-4.8 25.5 30 Mike Bibby
-4.5 31.8 36 Sam Cassell
-4.5 22.8 27 Steve Nash
-4.3 21.0 25 Jeff Foster
-3.9 14.4 18 Stephon Marbury
-3.7 0.6 4 Milt Palacio
The negative sign just means this is the bottom of the list, inverted. All these guys are high-TS%, high Ast/TO, or named Milt.
I can't seem to come up with an equivalent system that is as close to either of these as they are to one another. And I'm not sure that I want to. But what I've got right now is something I could call "expected win shares with an average team". And this just means there's no a priori bias toward guys on good/bad teams. A great player on a rotten team should produce substantial wins on an average team.
Here are players that look better in my "T2" system than in Justin's WS column:
M-J mT2 WS
14.1 29.1 15 Vince Carter
12.9 20.9 8 Allen Iverson
11.4 26.4 15 Lebron James
11.1 29.1 18 Paul Pierce
10.4 20.4 10 Jamal Crawford
9.9 28.9 19 Tracy Mcgrady
9.2 13.2 4 Drew Gooden
9.0 29.0 20 Zach Randolph
8.7 22.7 14 Jason Richardson
8.2 28.2 20 Baron Davis
As expected, all players from mediocre-to-bad clubs.
Comparing my little list to the PW list:
M-D mgT2 PW
11.9 26.4 14.7 Lebron James
11.4 20.9 9.6 Allen Iverson
11.3 29.1 18.0 Vince Carter
9.1 20.4 11.4 Jamal Crawford
8.9 18.1 9.3 Joe Johnson
8.9 13.2 4.5 Jalen Rose
8.7 28.9 20.4 Tracy Mcgrady
8.3 19.3 11.1 Antoine Walker
8.0 14.8 6.9 Quentin Richardson
7.9 12.9 5.1 Ronald Murray
Again, the PW figure is 3x that shown at b-r.com. Lebron's number is almost identical in the other 2 lists.
Back to top
View user's profile Send private message Send e-mail
Ed Küpfer
Joined: 30 Dec 2004
Posts: 785
Location: Toronto
PostPosted: Thu Feb 24, 2005 2:46 pm Post subject: Reply with quote
For years I've been using a Wins Above Replacement measure that gives out pseudo-Win Shares results. I calculate is like this:
Code:
WAR = Games * (Win% - x)
where Games is Oliverian wins plus losses, Win% is the ratio of wins to Games, and x is a replacement level. I typically set x at 10% or 20%, calling the results WAR10 and WAR20 respectively.
I compared WAR*3 to player WS over the last 5 season, and the results were very close. In the WAR20 sample, 1381 of the 2401 players (58%) came within +/- 3 WS. WAR10 was even better: 1846 players (77%) came within 3 WS. Finally I tried WAR5, using 5% as my replacement level WIN%, and got the best results of all: 2040 players (85%) were within 3 WS. I consider this supprt for the the WS methodology.
_________________
ed