Which stat predicted the 2015 the best? (Results here)

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colts18
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Which stat predicted the 2015 the best? (Results here)

Post by colts18 »

I decided to use 2014 stats and see which stats predicted the 2015 season. I tested a total of 9 stats. For players that didn't play the season before, I gave them a replacement level value. Here are the results:


R values:

Stat W-L% SRS
BPM 0.803 0.826
RPM 0.819 0.813
PI RAPM 0.799 0.794
NPI RAPM 0.741 0.759
WP/48 0.711 0.751
WS/48 0.720 0.745
14y RAPM 0.742 0.726
PER 0.702 0.717
USG% 0.585 0.549


BPM came out the best when compared to SRS while RPM was the best when compared W-L record. PER was the worst stat in terms of predictive value. Surprisingly, 14 year RAPM did poorly.
colts18
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Re: Which stat predicted the 2015 the best? (Results here)

Post by colts18 »

I tried out weighted Minutes played and it had a .759 R value to SRS, same as NPI RAPM. Who knew that simple minutes played from the previous season was so predictive?

A 50/50 BPM/RPM blend got me a .829 R value with SRS.
Last edited by colts18 on Tue Oct 27, 2015 3:50 am, edited 1 time in total.
AJbaskets
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Re: Which stat predicted the 2015 the best? (Results here)

Post by AJbaskets »

colts18 wrote:I tried out weighted Minutes played and it had a .759 R value to SRS, same as NPI RAPM. Who knew that simple minutes played from the previous season was so predictive?
How does weighted minutes work in this, adding up NBA minutes played the prior year for each team?
colts18
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Re: Which stat predicted the 2015 the best? (Results here)

Post by colts18 »

AJbaskets wrote:
colts18 wrote:I tried out weighted Minutes played and it had a .759 R value to SRS, same as NPI RAPM. Who knew that simple minutes played from the previous season was so predictive?
How does weighted minutes work in this, adding up NBA minutes played the prior year for each team?
Its 2015 Minutes played * 2014 Minutes Played. So a player plays 2000 MP in 2015. In 2014 he played 1000 MP. Its 2000*1000. Then do that for every player on the team and divide it total team minutes played. In this scenario a rookie has a 0 value.
sndesai1
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Re: Which stat predicted the 2015 the best? (Results here)

Post by sndesai1 »

colts18 wrote:I tried out weighted Minutes played and it had a .759 R value to SRS, same as NPI RAPM. Who knew that simple minutes played from the previous season was so predictive?

A 50/50 BPM/RPM blend got me a .829 R value with SRS.
i think permaximum has consistently mentioned the predictive power of minutes

i'm now curious if minutes or minutes per game has more power
colts18
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Re: Which stat predicted the 2015 the best? (Results here)

Post by colts18 »

sndesai1 wrote:
colts18 wrote:I tried out weighted Minutes played and it had a .759 R value to SRS, same as NPI RAPM. Who knew that simple minutes played from the previous season was so predictive?

A 50/50 BPM/RPM blend got me a .829 R value with SRS.
i think permaximum has consistently mentioned the predictive power of minutes

i'm now curious if minutes or minutes per game has more power
MPG has a .761 R value and that increases to .767 if you go by the Dsmok method of adding 4 games of 0 minutes.
browning
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Re: Which stat predicted the 2015 the best? (Results here)

Post by browning »

What measure of player success did you test against? Or was it the same stat, like last seasons PER is not predictive of this season's PER.
Nate
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Re: Which stat predicted the 2015 the best? (Results here)

Post by Nate »

browning wrote:What measure of player success did you test against? Or was it the same stat, like last seasons PER is not predictive of this season's PER.
I wouldn't mind if the whole testing procedure was described in a bit more detail.
colts18
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Re: Which stat predicted the 2015 the best? (Results here)

Post by colts18 »

Nate wrote:
browning wrote:What measure of player success did you test against? Or was it the same stat, like last seasons PER is not predictive of this season's PER.
I wouldn't mind if the whole testing procedure was described in a bit more detail.
I'll give an example with the Warriors. MP here is 2015 Minutes played. The rest of the stats are 2014 stats.

Code: Select all

	MP 	2014 PER	MP * PER
Leandro Barbosa	982	11.5	11293
Harrison Barnes	2318	9.8	22716.4
Andrew Bogut	1583	17	26911
Stephen Curry	2613	24.1	62973.3
Festus Ezeli	504	10	5040
Draymond Green	2490	12.7	31623
Justin Holiday	657	10	6570
Andre Iguodala	2069	13.7	28345.3
Ognjen Kuzmic	72	3.4	244.8
David Lee	904	19.1	17266.4
Shaun Livingston	1468	14.5	21286
James Michael McAdoo	137	10	1370
Brandon Rush	271	4.1	1111.1
Marreese Speights	1207	15.2	18346.4
Klay Thompson	2455	14.3	35106.5
Sum	19730	14.70872783	290203.2
Based on that, the Warriors get a weighted 14.71 PER based on 2015 MP. You can do that for every stat.

Code: Select all

Player	Tm	MP	PER	USG%	WS/48	BPM	RPM	NPI	PI	14y	WP48
Leandro Barbosa	GSW	982	11.5	20	0.058	-3.9	-1.52	0.7	-0.61	-0.9	0
Harrison Barnes	GSW	2318	9.8	16.8	0.07	-1.4	-2.88	-2.58	-2.11	-2.8	0.046
Andrew Bogut	GSW	1583	17	12.4	0.176	4.4	2.06	0.2	0.87	4	0.293
Stephen Curry	GSW	2613	24.1	28.3	0.225	7.4	6.24	3.46	5.18	3.1	0.263
Festus Ezeli	GSW	504	10	17	0.04	-2	-2	-2	-1.19	-1.3	0.04
Draymond Green	GSW	2490	12.7	14.8	0.119	2.8	3.5	2.89	3.36	2.3	0.191
Justin Holiday	GSW	657	10	17	0.04	-2	-2	-2	-0.17	0.3	0.04
Andre Iguodala	GSW	2069	13.7	13.3	0.135	3	6.63	5.31	6.31	4.6	0.241
Ognjen Kuzmic	GSW	72	3.4	13.3	-0.025	-5.2	-3.49	-1.74	-2.39	-3.1	-0.102
David Lee	GSW	904	19.1	24.3	0.16	0.8	1.22	2.74	1.07	-0.7	0.137
Shaun Livingston	GSW	1468	14.5	16.1	0.108	0.6	-0.6	0.26	-0.85	-0.7	0.151
James Michael McAdoo	GSW	137	10	17	0.04	-2	-2	-2	-2	-2	0.04
Brandon Rush	GSW	271	4.1	12.3	-0.05	-6.3	-2.78	-1.97	-3.06	-3.1	-0.033
Marreese Speights	GSW	1207	15.2	25.4	0.103	-5.2	-5.42	-2.79	-4.35	-5.6	0.013
Klay Thompson	GSW	2455	14.3	22.6	0.112	0.7	2.03	2.74	2.07	3.6	0.061

Here is every team:

Code: Select all

Row Labels	Sum of MP	Sum of xPER
ATL	19732	14.6
BOS	19880	13.4
BRK	19928	14.5
CHI	19881	13.6
CHO	19905	14.1
CLE	19779	18.1
DAL	19881	15.9
DEN	19881	14.3
DET	19827	14.2
GSW	19730	14.7
HOU	19804	14.6
IND	19855	12.8
LAC	19730	17.6
LAL	19932	13.0
MEM	19904	15.6
MIA	19732	14.2
MIL	19929	12.7
MIN	19806	12.6
NOP	19782	16.0
NYK	19855	12.6
OKC	19832	15.0
ORL	19755	12.7
PHI	19802	11.3
PHO	19879	16.2
POR	19856	15.5
SAC	19855	13.7
SAS	19955	16.2
TOR	19855	15.6
UTA	19705	13.6
WAS	19956	15.2

Based on that, I get the .717 correlation to SRS
Nate
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Re: Which stat predicted the 2015 the best? (Results here)

Post by Nate »

Thanks for the clarification.
Statman
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Re: Which stat predicted the 2015 the best? (Results here)

Post by Statman »

colts18 wrote: I'll give an example with the Warriors. MP here is 2015 Minutes played. The rest of the stats are 2014 stats.
Sorry, how did you account for rookies?

I had an idea I think I want to try for every rating I can find (ie, mine & the ones I find on b-r). Each player's rating would be calculated for every test season, then compiled at team level for correlations to actual team results:

(currentseasonRATING*minutesofcurrentseason+2*priorseasonRATING*minutesofpriorseason+2*nextseasonRATING*minutesofnextseason)/(currentminutes+2*priorminutes+2*nextminutes)

This takes away creating dummy ratings for rookies, and projecting "off" ratings on super small minute samples (ie, missed most season due to injury) to a much larger minute sample the next season. Kinda combines each rating's reflection of the current season (about 20% value, general sense) with its predictive correlations (80%). Doing prior AND next allows for generally eliminating age progression complications.

Modern box score stat era - could be done now for 33 seasons. Yearly correlations could give a better understanding of how well certain ratings adjust to a changing game (changes in pace, three frequency, Oreb frequency, etc).
Statman
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Re: Which stat predicted the 2015 the best? (Results here)

Post by Statman »

Sent you a pm - letting you know here because I always miss my messages, sometimes for weeks. I can't be the only one this happens to - right?
colts18
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Re: Which stat predicted the 2015 the best? (Results here)

Post by colts18 »

Statman wrote:
Sorry, how did you account for rookies?

I had an idea I think I want to try for every rating I can find (ie, mine & the ones I find on b-r). Each player's rating would be calculated for every test season, then compiled at team level for correlations to actual team results:

(currentseasonRATING*minutesofcurrentseason+2*priorseasonRATING*minutesofpriorseason+2*nextseasonRATING*minutesofnextseason)/(currentminutes+2*priorminutes+2*nextminutes)

This takes away creating dummy ratings for rookies, and projecting "off" ratings on super small minute samples (ie, missed most season due to injury) to a much larger minute sample the next season. Kinda combines each rating's reflection of the current season (about 20% value, general sense) with its predictive correlations (80%). Doing prior AND next allows for generally eliminating age progression complications.

Modern box score stat era - could be done now for 33 seasons. Yearly correlations could give a better understanding of how well certain ratings adjust to a changing game (changes in pace, three frequency, Oreb frequency, etc).
For players that didn't play the season before (includes Rookies), I gave them a replacement level value. That is -2 for RAPM, RPM, BPM. 0.04 for WS/48 and WP/48. And 10 PER, 17% usage.
colts18
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Re: Which stat predicted the 2015 the best? (Results here)

Post by colts18 »

Statman wrote:Sent you a pm - letting you know here because I always miss my messages, sometimes for weeks. I can't be the only one this happens to - right?
Here are the results for a few more stats

R value to SRS

WAR/48 0.761
HN/48 0.777
HNI 0.787

That would put those stats between NPI RAPM and PI RAPM.
bbstats
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Re: Which stat predicted the 2015 the best? (Results here)

Post by bbstats »

You should try Wins Produced.
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