76 replies to this topic

[j_wehr]

I wouldn't argue that RAPM will consistently outperform Vegas or that it's the clear winner over the other metrics, but that's not what we're talking about here. You have concluded that RAPM is useless (have you not?) on the basis of some players' RAPM not fitting with your judgment. But the conclusion simply doesn't follow from the premise. 

 

There's plenty of evidence that RAPM and other metrics are in fact useful -- if you aren't satisfied with one year's worth of results, go check out ESPN's stat geek smackdown -- and your only response is to keep pointing out cases that don't fit with your personal judgment?

 

I find your analysis of basketball very smart and very perceptive, but I'm continually frustrated by how you dismiss statistics as completely useless (or "just fun to play with") without giving good reason.

 

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2016, I'd like to hear more about why you think RAPM can't be used to rank players. I understand that it does so imperfectly, but do you have any reason to believe that it's much worse than other methods?

[timetodienow1234567]

I'll just point out the flaws in RAPM on our team alone. I'm using last year's stats.

 

Chandler Parsons is a horrible player by RAPM standards.

Negative offensive player, slightly positive defensive player.

 

James Anderson was our second best offensive player last year.......

 

Need I go on?

 

RAPM is a good metric, but like ALL advanced statistics, is HIGHLY flawed. I dislike when people try and treat it like it is something to swear by.

 

One more thing, here's a list of players BETTER than Parsons based on RAPM

 

Delfino

Anderson

Salmons

Biyombo

Acy 

Beverley

 

The list goes on and on.

[j_wehr]

"RAPM is a good metric, but like ALL advanced statistics, is HIGHLY flawed." HIGHLY flawed compared to what? Compared to your personal judgment?

[timetodienow1234567]

Lol. I guess so. My eye test tells me that Parsons is better than Anderson. But RAPM says otherwise.

 

I think I'll go with the eye test on that one. Which is my personal judgment. Are you trying to state that RAPM is right in this case. Do you believe that Anderson is better than Parsons?

[j_wehr]

If your point is that RAPM is imperfect, then why even waste breath? Of course it's imperfect. But so is your and my and everyone else's personal judgment. The important question is whether RAPM and other metrics are less flawed than your personal judgment. We could test that by having both you and RAPM predict this season's wins. Do you feel confident that you'd win? Want to bet on it?

[Mason Khamvilay]

 

I wouldn't argue that RAPM will consistently outperform Vegas or that it's the clear winner over the other metrics, but that's not what we're talking about here. You have concluded that RAPM is useless (have you not?) on the basis of some players' RAPM not fitting with your judgment. But the conclusion simply doesn't follow from the premise. 

 

There's plenty of evidence that RAPM and other metrics are in fact useful -- if you aren't satisfied with one year's worth of results, go check out ESPN's stat geek smackdown -- and your only response is to keep pointing out cases that don't fit with your personal judgment?

 

I find your analysis of basketball very smart and very perceptive, but I'm continually frustrated by how you dismiss statistics as completely useless (or "just fun to play with") without giving good reason.

 

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2016, I'd like to hear more about why you think RAPM can't be used to rank players. I understand that it does so imperfectly, but do you have any reason to believe that it's much worse than other methods?

 

There's no better stat than RAPM available to the public when it comes to ranking players. I just said that to make the RAPM haters happy. 

[Mason Khamvilay]

JG did bring up an interesting "anomaly" though--Lebron's defense. A DRAPM of 1.5 is obviously good for a SF, but the best defenders like Tony Allen, Paul George, Iguodala all have a DRAPM above 3. Is this really an "anomoly"? Or is Lebron's defense overrated?

 

Is it possible? King James defense just good, not elite?  

 

Once again, RAPM has caused us to ask an interesting question. Lets hear some answers!

[thejohnnygold]

What I think RAPM claims to do: improved version of +/-

 

What silly people think RAPM claims to do: rank players

 

And what is +/- for then?  2016, you are being childish and I am done with this.  I am sorry I used the word rank--I use that term to point towards the idea of categorically positioning players in terms of their affect on the game.  In short, it is a ranking system.  That's why when you look at it the players are listed in order from highest to lowest.

 

I do not think it ranks players.  I think it attempts to capture a players individual contribution to a basketball game on both sides of the ball.  I think "silly" people try to use it as a buoy to support their opinions of players.  I think it is incapable of dong so because I cannot in good faith take any of the numbers at face value due to my belief that there is a high percentage of numbers that are not in accordance with my subjective evaluation of them.

 

I like how nobody has touched Klay Thompson's -.2 ORAPM...nothing to see here....move along.  Come on.  If you are going to stand behind one you must stand behind them all or they lose meaning.  I am not going to take the time to list every single player I think has a glaring discrepancy.

 

2016, I see that you are trolling at this point.  The bottom line is that of the four main people involved in this discussion you have the least to contribute and must resort to juvenile antics.  You are better than this:

 

"There's no better stat than RAPM available to the public when it comes to ranking players. I just said that to make the RAPM haters happy."

 

So, between the quote at the top of this post to this one you have come full circle.  Turns out, much like RAPM scores your words lack any real substance and cannot be taken at face value.

 

j_wehr, I don't mean to be rude or dismissive (although I see that I have been) regarding RAPM.  I have not closed the door on it and if, in time, it proves to be useful I will gladly acknowledge that.  I personally have not yet been satisfied that this is the case.  I am interested to see if RAPM's win prediction ability is sustainable or just beginner's luck (so to speak).  Perhaps I should sit back and observe for a while and let more data and application come through before re-evaluating it.

 

I do rely on my own judgment quite a bit--and I am ok with that.  I am open to being corrected at any time, but I need to be convinced--not just told.  I feel like my reasons for disliking RAPM are sufficient; obviously, you feel differently about that.  I am less interested in win predictions which surely does nothing to bolster RAPM's value in my eyes.  I prefer match-ups, strengths vs. weakness, and I suppose a less macro view of the NBA season. 

 

At this point, I am going to steer away from this conversation.  I think I have said about all I can without repeating myself.  I'd be happy for others to continue it and I can just observe from the sidelines.

 

Also, please don't stop giving us statistical projections and breakdowns, j_wehr.  I appreciate the effort you put into them and you never know which one might be the one that converts me

 

One last thought, j_wehr.  Did you submit a list to the win prediction thread that Sir Thursday is running?  Technically, the entries are closed to members, but I bet he would allow an entry from an objective, stat-generated projection just to see if anyone can beat it.  I think a lot of people would enjoy that.

[Mason Khamvilay]

I agree completely that there is a phenomenal conversation going on here, lets keep the mood light though. 

[thejohnnygold]

JG did bring up an interesting "anomaly" though--Lebron's defense. A DRAPM of 1.5 is obviously good for a SF, but the best defenders like Tony Allen, Paul George, Iguodala all have a DRAPM above 3. Is this really an "anomoly"? Or is Lebron's defense overrated?

 

Is it possible? King James defense just good, not elite?  

 

Once again, RAPM has caused us to ask an interesting question. Lets hear some answers!

 

Allen and George each play in front of elite front court defenders.  Iguodala also had Javale McGee, Fareid, and Corey Brewer to play along with.

 

Lebron's got Bosh, Battier, Chris Andersen, Chalmers, and Haslem.

 

It's not that I think the first three don't deserve the recognition for being great defenders.  It's that a player's individual score is clearly affected by their teammates.  Which is why I keep saying it should just be a team stat based on line-ups.

[Mason Khamvilay]

Allen and George each play in front of elite front court defenders.  Iguodala also had Javale McGee, Fareid, and Corey Brewer to play along with.

 

Lebron's got Bosh, Battier, Chris Andersen, Chalmers, and Haslem.

 

It's not that I think the first three don't deserve the recognition for being great defenders.  It's that a player's individual score is clearly affected by their teammates.  Which is why I keep saying it should just be a team stat based on line-ups.

RAPM does a decent job of adjusting for this though. That's why Mario Chalmers has an extremely impressive +/- but a mediocre RAPM 

Edited by 2016Champions, 10 November 2013 - 09:56 PM.

[thejohnnygold]

I think Chalmers is one of Miami's best defenders...

[Mason Khamvilay]

I think Chalmers is one of Miami's best defenders...

Hence the fact he has an incredibly high DRAPM for someone only 6-1, but lets slow down for a second here....When I said Mario Chalmers +/- is incredibly high that includes the offensive end, so I don't get why you think I'm only talking about defense..

Edited by 2016Champions, 10 November 2013 - 10:17 PM.

[thejohnnygold]

I know +/- is for both ends.

 

What is Chalmer's RAPM?  I haven't looked.  I spoke of defense because that is what we have been talking about up to now.

[j_wehr]

Guys, sorry that I have been touchy about this. The reason this is not a lighthearted issue to me is that it seriously hurts my motivation to do interesting analyses when the results are dismissed by respected members of the site as completely useless. I like when people point out the flaws with a metric or with an analysis, but I despise when they leap to concluding that the results are therefore useless. (Your judgment is also flawed [and probably even more so than the metric], but I am not declaring your judgment useless.) I don't like having to spend my Wednesday afternoons defending my posts against faulty logic (or attacks on my personal credentials), and I don't like feeling that all of my work was futile.

 

I will move on now. I'm glad we were able to talk about this.

 

(If anyone would like to comment on the original post, I'm still very open to discussing. I'm surprised the Dwight performance issue isn't getting more attention.)

[rockets best fan]

 

Guys, sorry that I have been touchy about this. The reason this is not a lighthearted issue to me is that it seriously hurts my motivation to do interesting analyses when the results are dismissed by respected members of the site as completely useless. I like when people point out the flaws with a metric or with an analysis, but I despise when they leap to concluding that the results are therefore useless. (Your judgment is also flawed [and probably even more so than the metric], but I am not declaring your judgment useless.) I don't like having to spend my Wednesday afternoons defending my posts against faulty logic (or attacks on my personal credentials), and I don't like feeling that all of my work was futile.

 

I will move on now. I'm glad we were able to talk about this.

 

(If anyone would like to comment on the original post, I'm still very open to discussing. I'm surprised the Dwight performance issue isn't getting more attention.)

 

it's not that your work isn't respected because it is. however nearly all stats can be manipulated so no final conclusions should be drawn from them without also considering the whole picture. I am but a stat infant when it comes to some of you guys. however I use stats to confirm or discredit what the eye test tells me. I am an old timer when it comes to watching basketball. I usually don't need stats to know what I see. I have watched so much until listening to all the announcers have schooled me in what to look for. I like to look at stats but never draw a conclusion solely from them. I think that's the only point that most posters were trying to drive home here. it's nothing to get upset about because others don't share your view. actually I kind of like the work you presented......was good food  for thought, but in order to find my own understanding within the stat world I like to take in both the good and bad when it comes to one stat over another and reading some of these post help me do that. in other words I like knowing the limitation I'm dealing with. maybe try just presenting the work without the conclusions and leave the leave the posters to draw their own. however don't be discouraged your work is interesting to me

[RollingWave]

For Lebron at least, we should note tha the Heat was around 3 points worse defensively when he left the floor last year, that's significant but hardly other wordly,  (Asik and Dwight both had roughly double that effect)

 

When speaking in NBA defense it is very difficult to have a full ranging stat to cover everything, because different position do different things.