C/D: TS% & FGA are poor metrics for measuring efficency

[crazybranman360]

I love PPS because it really incorperates all aspects of scoring. The biggest complaint is that it heavily favors people who head to the line a lot but i think it should because the most effecient scorers should get to the line a lot.

[Agenda42]

Points per shot is a lousy metric for efficiency, which massively overstates the value of getting to the free throw line. I wouldn't say that TS% is a great metric, but it's better than PPS.

We need a stat for number of scoring attempts for a given player. This would easily correct for the inaccuracy of TS% due to its estimation of the impact of foul shots.

[EvanZ]

If we're talking about measuring "shooting" efficiency, I would recommend something along the line of the XeFG stat that Hoopdata keeps track of, or making separate comparisons at each distance/location on the floor. I would also correct for the assist effect (i.e. assisted shots have higher %'s compared to unassisted shots). I wrote a couple of posts recently about the 16-23 foot shot and some of these ideas:

"Monta Ellis and the Long Shot"

"Long Shots: Part Deux"

[floppymoose]

Nice posts, Evanz. I added a comment to your first one making the case that Ellis' fg%, and his number of attempts, is affected by him being the primary "bailout guy" on the team: the guy who is asked to create a shot when the offense has failed to generate anything and the shot clock is winding down. And also the guy asked to do the same thing when the Warriors are intentionally running clock late in a game with a lead. I'm sure Kobe suffers the same effect, and I would think a lot of teams put that burden primarily on one player.

[EvanZ]

Nice posts, Evanz. I added a comment to your first one making the case that Ellis' fg%, and his number of attempts, is affected by him being the primary "bailout guy" on the team: the guy who is asked to create a shot when the offense has failed to generate anything and the shot clock is winding down. And also the guy asked to do the same thing when the Warriors are intentionally running clock late in a game with a lead. I'm sure Kobe suffers the same effect, and I would think a lot of teams put that burden primarily on one player.

So, I'm not sure I can agree with that. It's a nice hypothesis, but if you look at the numbers (82games has them), he doesn't really shoot better in the middle of the shot clock compared to the last few seconds. Curry, on the other hand, is a much better shooter when he shoots in the middle of the shot clock. Interestingly, both shoot about the same percentage at the end of the shot clock.

Given that Curry and Ellis shoot about the same percentage at the end of the shot clock, and they both shoot about the same percentage of their shots at the end of the shot clock, and that Ellis doesn't really shoot any better or worse at the end of the shot clock compared to the middle, I would conclude that it's not "bail-out" shots that are the primary concern here. It's a testament to Ellis, actually, that his FG% doesn't dramatically decrease at the end of the shot clock, indicating that he is able to get off good shots. The problem I (still) have with Monta is that he takes too many unassisted shots in the middle of the shot clock, which he doesn't need to. If he could cut down on those, his efficiency would go up.

(Unfortunately, 82games doesn't break down shots by distance and shot clock time, so I can't know which shots are being taken.)

[floppymoose]

Well, we could both be right. He could be taking too many shots early in the clock, and also be suffering (even if not a lot) from having to take the tough shots for the team.

Another reason Monta might have for reduced efficiency, even in the middle of the shot clock, is that he plays almost all the minutes. This means when we have our scrubs out there, he's often the guy playing with them who is asked to carry the offense without the benefit of teammates who can take defensive pressure off him.

[EvanZ]

Well, we could both be right.

There can be only one!

[tclg]

I like efg and then looking at draw foul rate. TS I dont know I like to look at it but I dont really see it as the bes measure of efficiency. Though it is really cool to look at

[grimballer]

how about this:

pts/(fga + fta) = real pps?

looks more accurate than ts%.

[Rapcity_11]

how about this:

pts/(fga + fta) = real pps?

looks more accurate than ts%.

So FG's are worth twice as much as FT's?

[EvanZ]

I define OEFF (offensive efficiency) as follows:

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OEFF = 100*OFF/PU

where

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OFF = (1.0-astval)*(2.0-ppp)*afg2+(1.0-astval)*(3.0-ppp)*afg3+(2.0-ppp)*ufg2+(3.0-ppp)*ufg3+astval*(2.0-ppp)*ast2+astval*(3.0-ppp)*ast3-orbval*ppp*miss+ftm-ppp*(0.44*fta)+and1-ppp*tov-0.2*ppp*team_tov

Code: Select all

PU = (1-astval)*afg2+(1-astval)*afg3+ufg2+ufg3+astval*ast2+astval*ast3+orbval*miss+0.44*fta+tov

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astval=0.45
orbval=0.76
ppp=1.07

The top OEFF performers are obviously going to be PG by this metric (because of the assists):

TOP 10 OVERALL

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RANK   NAME   OEFF
1   Chris Paul   26.96
2   Steve Nash   26.18
3   Chauncey Billups   19.68
4   Ty Lawson   18.71
5   Deron Williams   16.31
6   Tony Parker   15.84
7   Beno Udrih   14.92
8   Jose Calderon   14.54
9   LeBron James   14.53
10   Kyle Lowry   14.50

TOP 10 NON-PG

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RANK   NAME   OEFF
9   LeBron James   14.53
12   Manu Ginobili   13.07
15   Nene Hilario   12.50
16   Arron Afflalo   12.35
18   Dirk Nowitzki   11.43
22   Tyson Chandler   10.97
23   Paul Pierce   10.81
25   Hedo Turkoglu   10.60
26   Pau Gasol   10.12
27   Dwyane Wade   9.93

BOTTOM 10

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RANK   NAME   OEFF
185   Darko Milicic   -22.57
184   Stephen Graham   -22.00
183   Shelden Williams   -21.63
182   Ben Wallace   -21.06
181   Linas Kleiza   -20.42
180   Samuel Dalembert   -19.97
179   Nazr Mohammed   -19.69
178   Jason Collins   -19.35
177   Marcus Camby   -18.83
176   Spencer Hawes   -18.66