Measuring Playmaking Ability of our Players

Maybe this guy's article can help. He has a playmaker equation as well...

"Playmaker Rating, which will henceforth be abbreviated as PlayRtg, is a fairly simple basketball metric that is quite easy to calculate.

The formula is as follows:

PlayRtg = USG*(PPG+2.26*APG-TPG)/(FGA+0.44*FTA+APG+TPG) where USG = Usage Rate, APG = Assists Per Game, PPG = Points Per Game, TPG = Turnovers Per Game, FGA = Field Goal Attempts Per Game, FTA = Free Throw Attempts Per Game

But how did I come up with it?

As you learned from the previous slide, it all started following a debate I had with a friend concerning the merits of assist-to-turnover ratio. He argued that it was a basic, simplistic way of analyzing point guard's playmaking abilities. Obviously, a good point guard would have a higher assist-to-turnover ratio because they'd generate more assists than turnovers.

Sure, I'm fine with that. But the stat can get better, and that's where our opinions diverged. He agreed that other things were more telling but didn't necessarily think it was necessary.

That's what I'm not fine with.

Playmaking, even for point guards, involves more than just finding open teammates. After all, if your point guard can score in the flow of the offense, isn't that just as valuable as accumulating another assist? To analyze a point guard's true playmaking ability, scoring needs to be taken into account.

Let's look at the numerator first. Point guards can do three things to end a possession when they have the ball: score, assist or turn it over. Obviously, points and assists are positive things while turnovers are negative.

Points per game needs no coefficient in front because the difference between two-pointers and three-pointers is contained within the stat.

I chose not to put a modifier in front of turnovers per game because a turnover leads to an extra possession for the opposing teams, and over the last few seasons the league average has typically been 1.0 points per possession if you round to the nearest tenth. Essentially, a turnover costs the offensive team a single point on average, and thus there is no need for a coefficient.

So, why the 2.26 in front of assists per game? Put quite simply, not every assist is worth exactly two points of offense. Quite a few assists lead to made three-pointers by teammates.

To find out exactly how often this was the case, I turned to HoopData.com, a site that breaks down where on-court field goals are made and which ones are assisted.

During the first half of the 2011-2012 season, 15 shots per game have been made at the rim, and 52.4 percent of them have been the direct results of assists, indicating that 7.86 assists per game are generated by shots made at the rim. From three to nine feet away, there are 4.2 made shots per game, and 39.6 percent of them are assisted, producing another 1.66 assists per game from this area.

From 10 to 15 feet away from the hoop, there are 2.8 makes per game, and 41.9 percent of them are assisted: another 1.17 assists per game. From 16 to 23 feet, there are 7.5 makes, and 59.5 percent of them are assisted: 4.46 more assists per game.

Finally, from behind the three-point arc, there are 6.3 makes per game, and 84.6 percent of them are the result of passes from teammates. That means that 5.32 assists per game lead to three points instead of two.

Adding it all up, there are 20.47 assists per game by the average team in the NBA. 15.15 of them result in two-point shots, leading to 30.3 points per game. The remaining 5.32 come on three-pointers and thus lead to 15.96 points per game. Adding those two numbers up, we see that those 20.47 assists per game lead, on average, to 46.26 points per game.

Simple division therefore tells us that each assist is worth 2.26 points (technically 2.25989) if the sample size is large enough."
http://bleacherreport.com/articles/...ll-metric-to-rank-nba-point-guard-play/page/2

 

Clutch BBS is all about our different opinions. If we all agreed there wouldn't be much to talk about.

 

Many of the people who find stats interest were here long before Morey or Lin

Interesting numbers d, I am having trouble reading the full width of the spreadsheet on my phone so I will have to check it out fully when I get home

 

Opinions are great, until you start stating them as facts.

See FOX news.

 

Why not use existing standardized advanced stats as a basis instead of having to do things like arbitrarily estimating multipliers to figure out assist attempts or FT attempts.

Source: http://www.basketball-reference.com/about/glossary.html

You may have noticed that USG% uses .44, instead of .50 used by the OP, as a multipler to calculate FTAs. I'll venture to guess that they were trying to take account for free throw attempts caused from and 1's.

We should just simplify everything and just add USG% and AST% together and used that to estimate overall ability to make plays.

Here are the results:

Code:

	 USG%   AST%  (USG% + AST%)
Harden	 28.2   23.8      52.0
Lin	 18.2   29.2      47.4

 

I posted this earlier on another thread, but this analysis only works if it is for the last few seconds of the shot clock or quarter, when a player MUST pass or shoot. Then, most of us can agree that giving it to Harden is fine. At the beginning of a possession, you've got to give it to the better passer, who can create the best shot, because Lin doesn't have to shoot, so you don't factor in shooting in the calculations. Then if the play breaks down and you need a shot at the end of the clock, swing it to Harden. Even Jordan was used like this when his team had poor PGs.

 

I don't get how you can add USG% and AST%, shouldn't we need to use USG% to normalize AST% to get something like an AST efficiency?

Put it this way, if two person has the same play making capability, wouldn't that the person have higher USG% got higher AST%? And here you add them up, then you are doubling the factor of USG%.....

 

If you look at the USG% formula, plays are defined as FGA, FTs, TOVs so it excludes assists. So USG% is really, in a simplified view, an estimated percentage of how many FGA, FTs, and TOVs a player has compared to his team's total FGA, FTs, and TOVs. So how can you use that percentage to somehow manipulate assists? That wouldn't make sense.

 

I do admit just adding the two is off because USG% takes shot attempts into account and AST% only considers FGs only. But I'm lazy and this is close enough for me. :grin:

 

Harden is a better offensive threat than Lin... end of story...

no need to compare playmaking ability between lin and harden etc etc.

end of the day, rockets makes decisions on the fly... what ever works at the moment will remain...

it is clear that their priority right now is to get as much wins than player development... but then again, if rockets make it the playoffs, it will be a huge experience gainer for the whole team in general.

 

How about just adding assists to the USG% formula?

100 * ((FGA + 0.44 * FTA + TOV + AST) * (Tm MP / 5)) / (MP * (Tm FGA + 0.44 * Tm FTA + Tm TOV + Tm AST))

 

The results:

Code:

Harden	28.55
Lin	22.02

 

Forget it this. I'm completely wrong with this formula.

 

Perhaps this will help:

PLX = PLA - PLM
as
PLA = FGA + 0.5*FTA + 1.5*AST + TOV
and
PLM = FGM + 0.5*FTM + AST
then
PLX = (FGA + 0.5*FTA + 1.5*AST + TOV ) - (FGM + 0.5*FTM + AST )
simplifies to
PLX = FGA - FGM + .5 FTA - .5 FTM +1.5 AST - 1 AST + TOV
simplifies to
PLX = FGA - FGM + .5 FTA - .5 FTM + .5 AST + TOV

In the final equation:
PLM_RTG = (LgPace/TmPace) * (36/MP) * (2*PLM - PLX)
simplifies to
PLM_RTG = (Team Constant C) * (2*PLM-PLX)
substituting PLX and PLM as defined above:
PLM_RTG = C*(2*(FGM + 0.5*FTM + AST)-(FGA - FGM + .5 FTA - .5 FTM + .5 AST + TOV))
simplifies to
PLM_RTG = C*(2FGM + FTM + 2AST - FGA +FGM-.5FTA+.5FTM-.5AST -TOV )
simplifies to
PLM_RTG = C*(3FGM +1.5 FTM + 1.5AST - FGA-.5FTA -TOV )
rearranged as
PLM_RTG = C*(3FGM-FGA +1.5 FTM-.5FTA + 1.5AST -TOV)



Therefore the basis of playmaking as defined by this formula is:

3FGM-FGA +1.5 FTM-.5FTA + 1.5AST -TOV

It is this formula which is then adjusted for pace.

Perhaps this will open up some insightful points into this rating system.

One thing I immediately note, is that turnovers are not weighted enough, as 1 made shot will cancel two turnovers.

 

Accepted. Now I have a different criticism.

Your formula does not account for how much a player has the ball in his hands. We need to normalize by this number, which I will call Ball Possession Rate, or BP%. Unfortunately, I know of no such statistic, or anything similar.

So let's fall back on usage rate as an estimate. Lin's usage rate, at 18.2 this season, is far lower than Harden's is 28.2. If we normalize to Harden's usage rate, we get

Lin 16.0
Harden 13.3

The new number for Lin, 16.0, is closer to the 17.1 he achieved last season, so is somewhat credible.

By this measure, and even by your definition of "playmaker", Lin is better than Harden.

 

you are right, I took USG% wrong. Looks like USG% indicates the percentage of direct attack one player take while he is on the floor compare to the team. Thus assist do not count into USG%. I think people on the board had use this number to argue Lin has less touch with ball kind of confused me there. Lin's drop of USG% directly relate to his less shooting, less FT attemps and also less TO.

However, I still don't get why you need to add USG%+AST%. I think just AST% would be a good indication on how good a play maker is in terms of how he is setting other people up. Then if you want to add the player's own scoring capability, maybe a simple player score/team score during the time the player is on the floor would be more accurate. (I don't know whether there is any stats tracking that or not).

I just can not wrap my head around the thought that TOV is a positive contributing factor in USG%, and you add that to a person's play making capability.

 

You can't scale usage rate like that.

The first thing that drops with increased usage rate is efficiency. That's almost a guaranteed.

 

I say this W. nothing else and nothing more.