PER Explanation/Rondo

[soap07]

Full disclosure, I consider myself a huge fan of sabremetrics. I think that some advanced stats can say much more than your run of the mill PPG, FG% etc.

I consider myself a bit perplexed by Hollinger's PER - and I am a huge fan of his.

PER Rankings this year....

http://insider.espn.go.com/nba/hollinger/statistics?&action=login&appRedirect=http://insider.espn.go.com/nba/hollinger/statistics

Some things make sense: The top 5 in PER this year in the NBA are LeBron, Chris Paul, Dwight Howard, Wade and Kobe. There is a reasonable argument to be made that those five, in that order, are the best players in the NBA.

However, go further down the list. Rajon Rondo clocks in at #47. Players with better PERs than Rajon: Devin Harris, Elton Brand, Brook Lopez, Tyrus Thomas, Andre Miller, Nene and Ryan Anderson.

Those players aren't slouches by any means. However, judging from watching any of these players this season, have any of them played close to Rondo's level? I don't think so.

It strikes me as odd that Rondo is a bonafide All-Star and probably a top-20 player in the league and he can't crack the top 45 in PER. What about him doesn't translate?

[Fafnir]

He doesn't shoot much. PER has a break even eFG% around 33% irc, that means that one of the ways you get a good PER is by shooting a lot.

[soap07]

He doesn't shoot much. PER has a break even eFG% around 33% irc, that means that one of the ways you get a good PER is by shooting a lot.

But some of the players on the list don't shoot all that much do they? Anderson, Nene, for example.

Additionally, Tim Duncan is 24th on the list and he barely shoots anymore. Is there that big of a difference between the amount of times TD/Rondo shoots that it causes a 20 spot difference?

[Brendan]

He also doesn't draw fouls or make free throws, two things PER weights highly IIRC.

[LooseCannon]

PER tends to undervalue defense, especially perimeter defense, and overvalue volume scorers.  Some also think it doesn't value rebounding enough.  Hollinger freely admits that his formula undervalues defensive specialists.

As a guard who has a lot of value tied up in his defense and who doesn't take a lot of shots and especially doesn't take a lot of three-point shots, Rondo seems to be the sort of player who will be undervalued by PER.

PER is an attempt to do a quick method of distilling box score data into a single number for the purpose of comparison.  This thread is probably going to become another bash Hollinger thread, but it should be noted that insisting that a better formula should incorporate data not found in conventional box scores is probably an unfair criticism.

[drza44]

A couple things:

1) PER is ok as a stat, but it has its flaws and you have to reasonably understand what they are if they stat is going to be of any use to you.

2) You can't just look at PER as your player rater, even as a just off-the-cuff rater, because its perspective is too narrow.  Conservatively there are 3 box score "advanced stats" regularly reported on the NBA through the season: PER (Hollinger and B-R), Win Shares (B-R), and Wins Produced (Berri) and at least a couple +/- based stats: On-court/off-court +/- (82games.com), in-season APM (BasketballValue.com).

My point?  Each of those has their advantages and disadvantages, and each one emphasizes a different part of the game.  PER is generally going to have more volume scorers and part-time role players doing well because they score more per minute (you mention Duncan, but he shoots 14.2 times per 36 minutes vs Rondo's 8.7 shots/36.  PER is a per-minute stat, and Rondo plays a lot more minutes without shooting/scoring much).  On the flip side, Wins Produced is a lot more about rebounding and assists so I'd bet money Rondo is a lot higher than 47th in the league by that stat.  On the flip side Win Shares is all about efficient scoring (i.e. points per shot), so I wouldn't expect Rondo to do as well there whereas Pierce and Ray are probably beasts in that stat.  And then the +/- stats give you a perspective on how much a particular player's output means to how his team actually produces.

Bottom line: I wouldn't worry about Rondo not ranking highly in PER.  The stat itself isn't conducive to recording the things he does well.  But I'd look at a cross section of all of the different "advanced" stats that are out there, and I'd bet that Rondo measures out better than 47th in the league.  In fact, in a nice cross-statistical comp I'd bet he's somewhere in the top-25 probably.

[BballTim]

Full disclosure, I consider myself a huge fan of sabremetrics. I think that some advanced stats can say much more than your run of the mill PPG, FG% etc.

I consider myself a bit perplexed by Hollinger's PER - and I am a huge fan of his.

PER Rankings this year....

http://insider.espn.go.com/nba/hollinger/statistics?&action=login&appRedirect=http://insider.espn.go.com/nba/hollinger/statistics

Some things make sense: The top 5 in PER this year in the NBA are LeBron, Chris Paul, Dwight Howard, Wade and Kobe. There is a reasonable argument to be made that those five, in that order, are the best players in the NBA.

However, go further down the list. Rajon Rondo clocks in at #47. Players with better PERs than Rajon: Devin Harris, Elton Brand, Brook Lopez, Tyrus Thomas, Andre Miller, Nene and Ryan Anderson.

Those players aren't slouches by any means. However, judging from watching any of these players this season, have any of them played close to Rondo's level? I don't think so.

It strikes me as odd that Rondo is a bonafide All-Star and probably a top-20 player in the league and he can't crack the top 45 in PER. What about him doesn't translate?

  It depends on which advanced metrics you look at. According to wages of win Rondo's 15th in the league, and he's been top 5-6 the last couple of years. Considering how much of the season he was struggling with injuries you can't expect him to be as high as he should in any rankings.

[Fan from VT]

PER also rewards efficient scoring, so drawing fouls, shooting a good free throw percentage, shooting good 3 point percentage, and shooting high field goal percentage (even if you don't shoot that often) will raise your PER.

[Greenbean]

It further highlights how unique Rondo is as a talent.

Hiolinger's model quantifies how good a player is by typical measures. Measures that years of following stats in the NBA has taught.

Ronod is an anomallu because he manages to (at his best) dominate a game by not even looking for his own shot. It is not typical of dominant players in this league so I would not expect a statistical model to recognize Rondo as a great player.

Rondo being so far down on the list does highlightn the fact that Rondo still has a lot of room to get better. He has a major weakness that right now he is able to play great basketball without. If he ever figures out how to get better at this weakness, you're probably looking at an MVP.

[greenpride32]

This isn't meant to be a knock on Rondo; he's a talented player who serves his role on a stacked team full of players that can also fill the stat sheet.

But if you want to look purely at statistics, which is what PER is, I can easily show you how much better Rondo's could really be.  Just lookup the stats of a guy named John Stockton.  In the years Stock averaged 13-14 dimes/game he still managed to score 17 points.  Stock got to the line and shot high percentages from 2, 3, and the free throw line.  He also got just as many steals as Rondo does while being far less of gambler on defense.

[Fafnir]

He doesn't shoot much. PER has a break even eFG% around 33% irc, that means that one of the ways you get a good PER is by shooting a lot.

But some of the players on the list don't shoot all that much do they? Anderson, Nene, for example.

Additionally, Tim Duncan is 24th on the list and he barely shoots anymore. Is there that big of a difference between the amount of times TD/Rondo shoots that it causes a 20 spot difference?

All of those players shoot alot more than Rondo, they also are all more efficient with their TS% because they make 3s or free throws. Getting to the line twice is basically a shot attempt after all.

You have to remember PER is minutes/pace adjusted, Tim Duncan plays a lot less than Rondo, so though he shoots only a little more than Rondo he scores at a better rate.

[Eja117]

I'd need to see things like what Bird and Jordan's pers were.  And Kevin McHale. and DJ.


To me this is like VH1's top 100 artists ranked by the artists.  I'd like to see that. I think players know players and can tell you who the best is and isn't.

Like Chris Bosh for example.   The players know he's not that good. You and I are catching on. They know.

[BballTim]

This isn't meant to be a knock on Rondo; he's a talented player who serves his role on a stacked team full of players that can also fill the stat sheet.

But if you want to look purely at statistics, which is what PER is, I can easily show you how much better Rondo's could really be.  Just lookup the stats of a guy named John Stockton.  In the years Stock averaged 13-14 dimes/game he still managed to score 17 points.  Stock got to the line and shot high percentages from 2, 3, and the free throw line.  He also got just as many steals as Rondo does while being far less of gambler on defense.

  Stockton was older than Rondo for the few years he averaged that many points, in fact he wasn't even a starter at the age Rondo is now. Rondo doesn't gamble as much on defense as he used to and he's more disruptive on defense than Stockton was.

[greenpride32]

This isn't meant to be a knock on Rondo; he's a talented player who serves his role on a stacked team full of players that can also fill the stat sheet.

But if you want to look purely at statistics, which is what PER is, I can easily show you how much better Rondo's could really be.  Just lookup the stats of a guy named John Stockton.  In the years Stock averaged 13-14 dimes/game he still managed to score 17 points.  Stock got to the line and shot high percentages from 2, 3, and the free throw line.  He also got just as many steals as Rondo does while being far less of gambler on defense.

  Stockton was older than Rondo for the few years he averaged that many points, in fact he wasn't even a starter at the age Rondo is now. Rondo doesn't gamble as much on defense as he used to and he's more disruptive on defense than Stockton was.

The OP is trying to make the arguement that Rondo should be in the top 20.  The point I was trying to make is Stockton probably would land in that range in his best seasons and Rondo's numbers are not even close.  I'm not trying to compare their careers in any way. 

[LooseCannon]

I'd need to see things like what Bird and Jordan's pers were.  And Kevin McHale. and DJ.

Jordan is #1 in career PER.  LeBron is #2 and Shaq is #3.  Bird is 19, between KG and Oscar Robertson.  Paul Pierce 50.  Ed Macauley 55.  McHale 64.  Cousy 72. Ray Allen 81. Robert Parish 82. Bill Russell is 96, but it is admitted by Hollinger that defensive specialists are underrated by PER.  If Rondo had enough games for the career leader list on basketball-reference.com, he would be ranked in the 160s.  DJ isn't in the top 250.