The Northcyde JumpShot Index

[TheNorthCydeRises]

What is the Northcyde Jump Shot Index ( NJSI )?

The NJSI is compiled by adding what a player shot from 2 point range via non-inside shots, to what a player shot from 3-point range. Those percentages are then added together, to give an indication of how well a player shoots from the outside.

For example, If a player shot .419 from 2 point range via non-inside shots, and .364 from 3-point range, his NJSI would be .783

To qualify to be listed on the NJSI, a player must have:

- had 65% of his total shot attempts be non-inside shots

- scored at least 7.5 points a game from these shots

- had at least 10% of his shots come from 3-point range

* NOTE #1: Exceptions will be made to add star players who may not qualify, or well known shooters who may not have the required 7.5 points per game from the outside. I'm not trying to give the NJSI for a player like JJ Redick, because he doesn't score enough from the outside per game, to qualify. ( LOL . . although his NJSI is .732 - - - and you'll see why his .732 index number keeps him on the bench. )

* NOTE #2: This is NOT an indicator of how great of an overall player that a certain player is. It does, however, give you insight on which guys can consistently make jumpshots, and what guys struggle to make them, for whatever reason.

To give a value to the NJSI, I've come up with this grading scale for the percentages:

Great: .900 or above

Highly Consistent: .850 - .899

Somewhat Consistent: .800 - .849

Somewhat Inconsistent: .750 - .799

Highly Inconsistent: .700 - .749

Horrible: below 700

When you see a player's name typed in GREEN, it indicates that he is close enough ( within .010 of the next category ) to be considered to move up into the next category. Next to a player's index number, you'll also see how many points he scored from non-inside shots in parenthesis. Hawks players are in BOLD.

Having said that, here is the Northcyde Jump Shot Index for the 2008 - 2009 regular season:

GREAT

J. Nelson: .957 ( 11.3 pts )

Morrow: .934 ( 7.7 pts )

Nash: .926 ( 10.5 pts )

HIGHLY CONSISTENT

Mo Williams: .899 ( 13.2 pts )

Ray Allen: .896 ( 12 pts )

Okur: .884 ( 9 pts )

Fisher: .873 ( 7.8 pts )

Korver: .865 ( 6.9 pts )

House: .864 ( 7.6 pts )

Gordon: .861 ( 13.2 pts )

Calderon: .859 ( 7.8 pts )

Terry: .858 ( 13.7 pts )

Kapono: .854 ( 7.2 pts )

SOMEWHAT CONSISTENT

Hinrich: .846 ( 7.6 pts )

Paul: .841 ( 11.7 pts )

R. Mason: .841 ( 9.6 pts )

Murphy: .840 ( 9 pts )

Finley: .839 ( 9.1 pts )

Bell: .836 ( 10.5 pts )

Nowitski: .833 ( 16.3 pts )

Blake: .833 ( 8.9 pts )

Pierce: .832 ( 10.4 pts )

OJ Mayo: .830 ( 12.2 pts )

JR Smith: .823 ( 9.8 pts )

Durant: .821 ( 12.4 pts )

Bibby: .816 ( 11.6 pts )

Delonte West: .815 ( 7.6 pts )

Jack: .813 ( 7.5 pts )

Bargnani: .811 ( 9.2 pts )

Outlaw: .811 ( 8.2 pts )

Roy: .808 ( 10.3 pts )

Salmons: .806 ( 9.2 pts )

Lewis: .802 ( 11.7 pts )

Granger: .800 ( 14.5 pts )

SOMEWHAT INCONSISTENT

Kidd: .798 ( 6.7 pts )

R. Wallace: .798 ( 9.4 pts )

Billups: .794 ( 10.1 pts )

Bryant: .790 ( 15.3 pts )

V. Carter: .789 ( 11.9 pts )

Kevin Martin: .789 ( 12.3 pts )

R. Jefferson: .787 ( 9.9 pts )

Hamilton: .787 ( 11.7 pts )

E. Gordon: .787 ( 7.8 pts )

A. Parker: .786 ( 7.3 pts )

R. Butler: .785 ( 8.2 pts )

J. Richardson: .779 ( 8.4 pts )

Barbosa: .777 ( 6.9 pts )

Villanueva: .774 ( 8.2 pts )

Joe Johnson: .772 ( 13.2 pts )

Gay: .771 ( 9.9 pts )

D. Williams: .765 ( 8.8 pts )

Flip Murray: .765 ( 6.9 pts )

Josh Howard: .761 ( 10.3 pts )

Gomes: .760 ( 8.4 pts )

Mo Evans: .760 ( 4.6 pts )

Marvin Williams: .754 ( 6.1 pts )

Stoyakovic: .754 ( 10.4 pts )

Harrington: .753 ( 10.8 pts )

C. Anthony: .750 ( 9.8 pts )

Redd: .750 ( 11.1 pts )

HIGHLY INCONSISTENT

Wade: .748 ( 12.7 pts )

N. Robinson: .747 ( 8.9 pts )

Foye: .744 ( 9.2 pts )

Artest: .742 ( 10.5 pts )

Jamison: .741 ( 10.1 pts )

Ginoboli: .739 ( 7.2 pts )

Crawford: .738 ( 12 pts )

Turkoglu: .737 ( 8.9 pts )

W. Chandler: .737 ( 8.4 pts )

Green: .735 ( 7.6 pts )

McGrady: .726 ( 9 pts )

L. James: .719 ( 10.9 pts )

Cook: .717 ( 7.9 pts )

Alston: .712 ( 7.5 pts )

C. Butler: .711 ( 9.6 pts )

Felton: .702 ( 7.8 pts )

HORRIBLE

S. Jackson: .697 ( 10.3 pts )

Iverson: .681 ( 8.3 pts )

Iguodala: .655 ( 6.9 pts )

Baron Davis: .635 ( 8.1 pts )

[mrhonline]

Adding them would indicate they have equal value, no?

Shouldn't the 3pt percentage be added at 1.5 times the value of the 2pt. percentage?

[txsting]

Adding them would indicate they have equal value, no?

Shouldn't the 3pt percentage be added at 1.5 times the value of the 2pt. percentage?

Agreed. You need to first covert the 3pt. percentage to a 2pt percentage if you want to add them

Ex. 33% 3pt = 50% 2pt.

You also need to take into account how much the player shot from both 2 and 3.

Under your current system, some guy who was 6-9 from the 3pt stripe and only 300/1000 from the 2pt area would rank as 'GREAT'.

[TheNorthCydeRises]

No and No to both of you. This is totally different from the eFG.

While the eFG is a good way to adjust 3pt shooting to actual scoring, it does kind of skew how good of a shooter someone is. Because in reality, 2 - 6 FGs is 2 - 6 FGs. It may have a different point value if you made 2 threes compared to 2 twos . . . but you still missed 4 shots. If you hit those first two shots, but then missed your next 4, those 4 missed shots become potential killers.

Those 4 missed shots could lead to 8 - 12 points on the other end.

The reason I gave those parameters about only listing those guys who take 65% via jumpshots, 7.5 points, and 10% of shots being 3's, is to eliminate those players like a LaMarcus Aldridge, who takes 65% of his shots from the outside, but only 2% of those shots come from 3-point range.

If anything, I should probably raise the parameters of the minimum 3-point shot percentage to 15% or 20%, to really address those guys who are "shooters", or who think they are shooters. 15% is probably the optimum number. Another tweak is to raise the minimun number of outside shots to 70%, but that would eliminate a few people who take a lot of shots from the outside.

JJ was inconsistent this year with his jumper, mainly because he took a lot of tough shots. This index accurately points that out.

[TheNorthCydeRises]

If this isn't somewhat accurate, do you think there any person that you think is ranked too high or too low?

[mrhonline]

My question remains this - what is the value of a 20 foot jumper? Do you really want guys shooting that in today's game?

[TheNorthCydeRises]

That's why adding a Josh Smith to this list, would be unfair to him, because his game doesn't necessarily depend on the outside shot. Although if I were to do a NJSI on him, it would be .621, and the reason why people are so against him shooting jumpers.

Rajon Rondo is the same way. His game isn't an "outside" type game. But if you do a NJSI on him, it would be .672, an accurate reflection of his horrible jumpshooting.

[TheNorthCydeRises]

My question remains this - what is the value of a 20 foot jumper? Do you really want guys shooting that in today's game?

You mean the 20 foot jumper that Kobe kills people with?

The 20 foot jumper that Dirk kills people with?

The 20 foot jumper that has made Deron Williams into one of the best pick and roll PGs in the game?

The horrible thing about the 3 point line, is that bad shooters are encouraged to shoot that shot, and not take the 20 fooot jumper that they can make, because the 3-point shot is worth more. That's why you see all of these streaky shooters in this league, instead of the mid-range assassins that used to kill this league.

[TheNorthCydeRises]

Hawks playoff NJSI:

Bibby: .903

Evans: .812

Johnson: .790

Murray: .704

Williams: .439 ( .167 from 3-point range & .272 on 2-point jumpshots . . sample size very small though )

Smith: .390 ( NOTE: Only 9% of Smith's shots came from 3-point range, so that would disqualify him to be ranked in the NJSI. He shot .133 from 3-point range . . and .286 2-pt jumpshots )

[mrhonline]

You mean the 20 foot jumper that Kobe kills people with?

The 20 foot jumper that Dirk kills people with?

The 20 foot jumper that has made Deron Williams into one of the best pick and roll PGs in the game?

The horrible thing about the 3 point line, is that bad shooters are encouraged to shoot that shot, and not take the 20 fooot jumper that they can make, because the 3-point shot is worth more. That's why you see all of these streaky shooters in this league, instead of the mid-range assassins that used to kill this league.

Your argument is that the 20-foot jumpshoot should be used more often because Kobe, Kirk, and Deron are good at it?

[coachx]

Adding them would indicate they have equal value, no?

Shouldn't the 3pt percentage be added at 1.5 times the value of the 2pt. percentage?

Agreed !

Any stat that does not recognize a made 3 pointer is more valuable then a made 2 pointer is a stat that is off the mark.

I personally think FG EFF % accomplishes all you need to know.

Edited June 29, 2009 by coachx

[txsting]

Agreed !

Any stat that does not recognize a made 3 pointer is more valuable then a made 2 pointer is a stat that is off the mark.

I personally think FG EFF % accomplishes all you need to know.

Yeah I think points/attempts is a great mark. Anything >1 is very good. If you have a way of getting rid of the inside shots from the data, then you really have a nice picture of jump shot efficiency.

Northcyde, what source of data did you use to separate out inside vs. outside shots? NBA Hot Spots?

[mrhonline]

Using this: http://www.nba.com/hotspots/, I have Marvin's NJSI as .800.

There's also this:

http://www.82games.com/0809/FGSORT7.HTM

A good article:

http://blogs.wsj.com/dailyfix/2009/03/17/t...should-be-lost/

Edited June 29, 2009 by mrhonline

[TheNorthCydeRises]

Yeah I think points/attempts is a great mark. Anything >1 is very good. If you have a way of getting rid of the inside shots from the data, then you really have a nice picture of jump shot efficiency.

Northcyde, what source of data did you use to separate out inside vs. outside shots? NBA Hot Spots?

No. This is my source.

http://www.82games.com/0809/FGSORT7.HTM

The detailed player shooting stats go from 3-point shots, inside shots, and 2 point jumpshots.

But like I said, this will not be accurate for everybody that doesn't take a decent number of 3-point shots. The key is to ONLY look at the 3 point attempts and 2-point jumpshot attempts.

You can't look at this from the eFG perspective, because the eFG can skew how well someone shoots, if they make a lot of threes. The NJSI doesn't measure points coming from those shots. It simply gives a decent idea of who shoots well, who is inconsistent, and who is horrible.

I'll ask again. Is there any player that seems to be out of place when looking at the NJSI?

[mrhonline]

I'll ask again. Is there any player that seems to be out of place when looking at the NJSI?

Out of place for what???

I still don't understand what this is supposed to measure.

[TheNorthCydeRises]

Using this: http://www.nba.com/hotspots/, I have Marvin's NJSI as .800.

Marvin's NJSI is around .800 ( I calculated .798 ) if you use the parameters of NBA hotspots. But I think there is a difference in what 82games.com counts as a jumpshot. From what I can see on NBA Hotspots, their zone just inside the 3-point line, seems to extend from 15 feet out to the 3 point line.

By that account, a 12 foot floater in the lane by JJ wouldn't be considered a jumpshot, but an inside shot, by NBA hotspots. I think that's the difference.

If Marvin drives to the hole, but takes a running shot 10 feet away from the basket, I think 82games still considers that a jumpshot.

[TheNorthCydeRises]

Out of place for what???

I still don't understand what this is supposed to measure.

It's measuring the shooting that takes place in the game, that isn't considered to be an inside shot. But unlike the eFG, I'm not tryiing to adjust the 3 point percentage, to adjust for the point differential between a 2 point jumpshot, and a 3 point shot.

A guy goes 6 - 12, but only shoots 2-point jumpshots. He shoots 50% and scores 12 points.

Another guy goes 4- 12, but only shoots 3 point shots. He shoots 33% and scores 12 points.

Because of the eFG, people look at that 6 - 12 and 4 - 12 as being equal, because they got you the same amount of points. But the reality is that the other guy missed 2 more shots, regardless of where the shot was from.

The 4 - 12 from 3-point range is usually seen as a bad percentage for a guy shooting 3-pointers. But somehow, all that is null and void, because he got you the same amount of points as the guy who shot 6 - 12. But the 6- 12 from 2-point jumpers, is considered great.

The categories that the players are placed in, according to their index number, shows just who are the decent shooters, and who's not.

When I say "out of place", I'm saying does this index overrate or underrate a player, according to the category he's placed in.

[Gray Mule]

It's measuring the shooting that takes place in the game, that isn't considered to be an inside shot. But unlike the eFG, I'm not tryiing to adjust the 3 point percentage, to adjust for the point differential between a 2 point jumpshot, and a 3 point shot.

A guy goes 6 - 12, but only shoots 2-point jumpshots. He shoots 50% and scores 12 points.

Another guy goes 4- 12, but only shoots 3 point shots. He shoots 33% and scores 12 points.

Because of the eFG, people look at that 6 - 12 and 4 - 12 as being equal, because they got you the same amount of points. But the reality is that the other guy missed 2 more shots, regardless of where the shot was from.

The 4 - 12 from 3-point range is usually seen as a bad percentage for a guy shooting 3-pointers. But somehow, all that is null and void, because he got you the same amount of points as the guy who shot 6 - 12. But the 6- 12 from 2-point jumpers, is considered great.

The categories that the players are placed in, according to their index number, shows just who are the decent shooters, and who's not.

When I say "out of place", I'm saying does this index overrate or underrate a player, according to the category he's placed in.

The great difference, as you point out, both players scored the same number of points

BUT the player who shot 4-12 from the 3 point range left 8 rebounds out there for

the opponent to grab (potentially) and score for the opponent while the guy who

shot 6-12 from the 2 point range scored the same number of points AND left 6 rebounds

out there for the opponent to grab.

So, the real question that we have is: Who gets the rebound? If you have a great

rebounding team, it may not matter very much BUT if you have a poor rebounding

team, the guy shooting all those 3's may cause a lot of problems.

:angel19:

[mrhonline]

The great difference, as you point out, both players scored the same number of points

BUT the player who shot 4-12 from the 3 point range left 8 rebounds out there for

the opponent to grab (potentially) and score for the opponent while the guy who

shot 6-12 from the 2 point range scored the same number of points AND left 6 rebounds

out there for the opponent to grab.

So, the real question that we have is: Who gets the rebound? If you have a great

rebounding team, it may not matter very much BUT if you have a poor rebounding

team, the guy shooting all those 3's may cause a lot of problems.

:angel19:

And, in one post, Gray Mule dissected the primary statistical question regarding offensive stats of the modern era. :-)

The most popular line of thinking is that the three-point shot creates more opportunities for offensive rebounds because it pulls rebounders away from the basket.

[AHF]

I personally think FG EFF % accomplishes all you need to know.

I can see the value in taking out dunks, layups, and other interior scoring and focusing on jump shots but I agree that the eFG% forumula as applied only to jump shots would seem to be the most meaninful because it takes into account the value of 3's and the distribution of each player's shot selection.