Comments on: Alternatives to the BBR Rankings: The Maximum Likelihood Method http://www.basketball-reference.com/blog/?p=4398 NBA & ABA Basketball Statistics & History Mon, 21 Nov 2011 20:56:04 +0000 hourly 1 https://wordpress.org/?v=4.6 By: Jesse http://www.basketball-reference.com/blog/?p=4398&cpage=1#comment-15895 Wed, 07 Apr 2010 19:31:53 +0000 http://www.basketball-reference.com/blog/?p=4398#comment-15895 How would one go about translating the power ratings given above to points? Expressing power ratings as points or wins or what-have-you... something real... seems to be more understandable than using a dimensionless number.

The idea I had was to find the league-wide HCA, and then translate the power ratings into points based on that. So if the HCA league-wide is 3 points, then, for example, Cleveland's rating is +6.49 points.

Also, I know that Neil said the ratings don't add to zero exactly, but if the sum is as close to zero as it is (0.00002), it's not worth worrying about.

]]> By: Mike G http://www.basketball-reference.com/blog/?p=4398&cpage=1#comment-14087 Fri, 15 Jan 2010 11:56:28 +0000 http://www.basketball-reference.com/blog/?p=4398#comment-14087 "How does eWins handle defense? If it doesn't make a team adjustment at some point, it's essentially saying, '100% of a player's defensive ability is described by his blocks, steals, and DReb.'"

eWins makes team adjustments all along the process. Points and assists are scaled to opponent points, rebounds to opp. reb.

Monta Ellis is averaging 26 PPG, but for a team that allows 112 PPG. So, that 26 Pts are just (100/112) 89% as much a contribution as they'd be for an avg team. For Hou he might be expected to avg 23; for Cha, perhaps 21.5.

eWins doesn't bother to distinguish between offense and defense per se. Rather, productivity is scaled to 'rest of the league' performance in the games a player is in : vs GSW, in Ellis' case.

]]> By: Neil Paine http://www.basketball-reference.com/blog/?p=4398&cpage=1#comment-14074 Thu, 14 Jan 2010 16:22:16 +0000 http://www.basketball-reference.com/blog/?p=4398#comment-14074 Mike, I don't really see how you can properly factor in defense as half of the game (as WS does) and not have fluctuations like that when a player moves from a good defensive team to a bad one. How does eWins handle defense? If it doesn't make a team adjustment at some point, it's essentially saying, "100% of a player's defensive ability is described by his blocks, steals, and DReb." I don't know how Justin feels, but I'd rather be "wrong" on a few players by adjusting the defensive component of the stat for the team's defensive rating than claim that blocks, steals, and DReb describe 100% of a player's defensive contribution.

]]> By: Mike G http://www.basketball-reference.com/blog/?p=4398&cpage=1#comment-14072 Thu, 14 Jan 2010 15:02:39 +0000 http://www.basketball-reference.com/blog/?p=4398#comment-14072 According to this page:
http://www.basketball-reference.com/players/t/turkohe01.html

Hedo Turkoglu, from '03 in Sac, to '04 in SA, to '05 in Orl, had his DRtg go from 102 to 94 to 110; his DWS from 1.5 to 4.5 to 1.0.
DWS per 484 minutes (.50 = avg) moved from .62 to 1.05 to .28 in this time, while his OWS/484 rose steadily from .47 to .52 to .60 .

Last year to this year, his DWS/484 has gone from .76 to .04, Orl to Tor.
This is "incredibly team-reliant".

Meanwhile, what about a column for WS per X minutes?

]]> By: Justin Kubatko http://www.basketball-reference.com/blog/?p=4398&cpage=1#comment-14071 Thu, 14 Jan 2010 13:17:18 +0000 http://www.basketball-reference.com/blog/?p=4398#comment-14071 Ryan wrote:

I've noticed an increase, especially on BBR's blog, of measuring a player's greatness/talent by Win Shares. Win Shares, to my understanding, is incredibly team-reliant.

This is a common misperception. Two players (playing on different teams) with the same playing time, same number of possessions, same offensive rating, and same defensive rating will have the same number of Win Shares. Now, defensive rating does have a team component, but all in all I would not call Win Shares "incredibly team-reliant". More details are available here.

]]> By: Walter http://www.basketball-reference.com/blog/?p=4398&cpage=1#comment-14069 Thu, 14 Jan 2010 06:44:20 +0000 http://www.basketball-reference.com/blog/?p=4398#comment-14069 I love the use of MLE here. I think it would be interesting to use MLE with margin of victory instead of the binary win/loss. I doubt the results would be significantly different but it would be interesting none-the-less.

Keep up the good work.

]]> By: Ryan http://www.basketball-reference.com/blog/?p=4398&cpage=1#comment-14068 Thu, 14 Jan 2010 05:39:16 +0000 http://www.basketball-reference.com/blog/?p=4398#comment-14068 Neil, I know this isn't the appropriate place to post this question, but I'm on the run. I'll get around to reading & responding to this blog tonight or tomorrow.

I've noticed an increase, especially on BBR's blog, of measuring a player's greatness/talent by Win Shares. Win Shares, to my understanding, is incredibly team-reliant. Wouldn't it make more sense, perhaps, to measure a player's individual ability and impact by WS%? Adding a WS% column to BBR's advanced stats, IMO, would be beneficial. If Jordan's team won 50 games, while James' won 66, yet both have comparable WS then the disparity should be made readily available in an alternative form of WS (in this case, WS%).

Cheers.

Unless of course, my understanding of WS is completely wrong.

]]> By: Ryan J. Parker http://www.basketball-reference.com/blog/?p=4398&cpage=1#comment-14059 Wed, 13 Jan 2010 19:24:53 +0000 http://www.basketball-reference.com/blog/?p=4398#comment-14059 Yay for MLE :)

It might have just been easier to say that this is a logistic regression, but I like getting people to think about the idea of maximum likelihood.

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