ElGee wrote:Gideon wrote:ElGee wrote:
They have the two best career on/offs in the regular season. According to BBR, Kevin Garnett is the best in the playoffs for any player career 2001-2012.
I focused on regular season on/off, because I think sample size is a huge factor with on/off... for that reason I would put much more stock in regular season on/off (which in the case of KG incorporates almost exactly 10 times the number of games as the playoffs... I assume this is similar for most top players). I've seen bizarre on/offs with even 2 or 3 full seasons of sample size, but once you're looking at multiple seasons up to a career, it starts to seem like a pretty good indicator.
Obviously, KG is a great player (I think he might be 3rd in RS on/off, anyway after Dirk and LeBron), so I'm not saying it's an anomaly he's the leader in on/off for the playoffs... but for a stat that is SO dependent on sample size, I would be much more inclined to focus more on wherever there's a significant sample size (which is clearly RS in this case). Garnett has played 114 playoff games since 2001... that's barely more than a single season, which just is not a reliable sample size for on/off.
*Actually, thinking about this more... the very best solution seems like it would be to just combine numbers from RS and PS and get the largest sample size possible for on/off. That seems like it would be the best indicator. I don't have time to do that for LeBron, Dirk, and KG at this moment, but judging by a quick glance at the numbers, I would expect those to be the top 3 guys using that metric, with LeBron first and Dirk and KG very close for 2nd.
Gideon I don't actually see on/off that way. I don't think you are increasing accuracy by increasing sample at all. I haven't tested variation after 50 games say, versus 80, but I don't see that as the issue. I think the stat just isn't particularly accurate for measuring goodness. It is what it is, which is first and foremost an indicator of what's happening with a guy on the court versus off it. That's interesting. It's valuable. It's also a conditional measure, and for the purpose of measuring player goodness, is subject to some major confounding variables like teammates and opponents (this is why people try and adjust it).
I don't see increasing the sample as changing these issues at all. And similarly, I don't see the samples for multi-year PS, which I can post tomorrow, as being subject to a small sample. For his career, KG has 4800 minutes on and 1200 minutes off -- what sample-size argument can you come up with to object to that?
A bigger sample size increases accuracy with every other stat... why wouldn't it do so with on/off?
A player who has a "true" scoring avg of 20 ppg could easily get hot and average 35 ppg over a 5-game sample; over a season, that player will almost never be as far from his "true" average as he was during that 5-game sample, but the season can certainly still be an outlier (such as Michael Adams's 26.5 ppg season); over a 10-year-career, that player's ppg is going to be much closer to a "true" average (obv variables such as era/pace, system, etc. should be considered, too, but you get the idea).
On/off isn't any different. The bigger the sample size, the more likely it is to be accurate. Flip a coin 10 times, and 80% heads could easily happen... flip the coin 1000 times, and heads is always going to be very close to 50%. With on/off it's a little more complex than the coin-flip situation, since there are variables that affect on/off and should be evaluated to put it into context (just like with the ppg example)... but that's true of every other stat in basketball, as well.
The principle of bigger sample size being more accurate for on/off can also be demonstrated directly with on/off itself by observing that many players have a single season on/off that is higher than the highest career on-off since 2001. I'm not referring to a small number of elite seasons that "deserve" to be higher than LeBron or Dirk or KG's career on/off... it's a phenomenon that clearly has to do with sample size. For example, Baron Davis's on/off for the 06/07 season is higher than Dirk and Lebron's league-best career RS on/offs. There are plenty of similar examples of single-season outliers like this. However, there are zero career outliers with a normal-length career to anywhere near this extent that I've come across... I guess it's possible I'm missing one or two, but that would still be vastly less than with single seasons.
Here's an on/off leaderboard from 07-08 (http://www.82games.com/ONSORT6.HTM). #2 and #3 on that list are Jamison and Carter... and there are plenty of other surprises/outliers on it. The career RS on/off leaderboard has Dirk, LeBron, and KG as the top three, and many other stars right behind them. There are just way fewer outliers on the career list than for any single season... I think sample size has to be the reason for this.
When we look at the PS -- (most stars have the equivalent of between about half a season to a little over a season worth of PS games to evaluate) -- there are also many outliers. For example, Chris Paul's PS career on/off (over 39 games) is -2.0. This is obviously not representative of Paul's true impact. However, Paul's RS career on/off (over a 555-game sample size) is +8.2, which is star-level and exactly the same as Tim Duncan. In this case, the bigger sample size has produced a much more accurate result, and I could show example after example like this.
I'm not saying on/off is a magic end-all, be-all stat (although I do like it more than most seem to on this forum). I've found to it be pretty valuable over a large sample size, and not very valuable over a small sample size. This is just speculation on my part, but I think the complexities involved with on/off that you touched upon (rotations, system, opponents, pace, etc.) are complex enough that a larger sample size is needed to naturally adjust for them than with many other stats that are less variable-dependent.






