In the first 4 installments of this series, we dealt only with advanced individual player stats. Now we’re going to move on to teams.
Some may say that the only important team statistic is winning percentage and I wouldn’t argue all that hard with this point of view. Still, the advanced team stats can provide additional insight into why a team’s winning percentage is what it is, so we’ll take a look.
Beyond Wins and Losses…and Pythagoras, the Hoops Stats Geek
Most of us are fond of the saying “a win is a win.” Stats guys aren’t. It’s their nature to try to find extra meaning from things most folks see as simple. Not only is this not a bad thing, if we’re honest with ourselves, most of us don’t really believe that a win is a win either. If your favorite team beats a bad team by 20 points, you probably feel better about things than if they just eked the thing out. When the latter happens, you probably start your assessment with , “Yeah, we won, but…” The quality of the competition also matters to most of us. If your team beats the Miami Heat or the LA Lakers it probably gives you a bigger buzz than if you beat a doormat.
What the stats gurus do here isn’t all that tricky. They keep track of margin of victory (MOV) as well as strength of schedule (SOS) to come up with alternative team rankings.
A team that outscores its opponents by an average of 7 points per game (+7 MOV) is presumably better than a team that only outscores its opponents by a single point (+1MOV). A team with a MOV of -3 is presumably better than a team that has a -8 MOV. SOS takes the MOVs of all the teams you’ve played and provides a number, positive (stronger than average schedule), negative (weaker than average schedule) or zero (a neutral/average schedule). As the stats guys see it, if your team has a high positive MOV and a high positive SOS, you have yourself one damn fine team.
In one of the least surprising developments in the history of sports statistics, the statisticians combined the MOV and SOS into a single stat. Then they showed what I suspect was an inadvertent sense of humor by calling their new stat the “Simple Rating System (SRS)". When I saw the word “simple” in the name, I started to laugh. Then I followed the link below to an article that describes the methodology and I laughed so hard I hurt myself (you’ve been warned):
The top teams in the NBA by SRS? Here ya go:
Chicago Bulls – 6.51
Heat – 6.45
Lakers – 6.32
San Antonio Spurs – 5.91
Boston Celtics – 5.13
I’d really love to argue with these, but must admit that they’re very damn close to what my eyeballs have been telling me, so they may be onto something here. By the way, from time to time you may hear or read about a team’s “Power Rating.” There are lots of different methods for these, but it’s a good bet that MOV and SOS are in the mix.
So about now (if you’re still awake), you may be thinking “Wait a minute! What about Pythagoras? What the heck does he have to do with this stuff” From high school, you may remember that Pythagoras was a Greek philosopher who dabbled in math and came up with something called the Pythagorean Theorem (yeah, some say he didn’t, but who cares?) which dealt with triangles and stuff. None of this matters, but some stats guys have used Pythagoras’s mathematical musings to come up something called “Pythagorean wins” and “Pythagorean losses.” These essentially take a team’s MOV, massages these numbers with some Pythagorean ju-ju, and then predicts the number of wins and losses a team should have. If you really want more specifics on the ju-ju, have at it:
The main advantage of the “Pythagorean standings” over the MOV ratings is that they’re, well, standings so you can easily compare what Pythagoras would predict to what has actually happen. For instance, we all know that the Spurs have the best record in the NBA and it’s not really all that close. Their 57-17 record is 3.5 games ahead of the second-best Bulls (53-20). However, as Pythagoras sees things, the Spurs are no better than tied (with the Orlando Magic) for the 5th-best team in the NBA behind the Bulls (54-19 Pythagorean W-L), Heat (54-20), Lakers (52-21) and Celtics (51-22). Pythagoras has the Spurs and Magic at 51-23.
Many stats geeks believe that Pythagorean win-loss records is a better indicator of the true quality of a team and therefore a superior predictor of playoff success. Being a Bulls’ fan, I hope Pythagoras is right, but have to be honest and say that I don’t buy it (last season the World Champion Lakers were tied for the 5th-best Pythagorean regular season record). However, one thing comparing teams Pythagorean versus actual records is good for is to get a quick sense of how well or poorly a team does in close games. For example, since the Spurs have a much better actual record than their MOV-based Pythagorean record, it’s likely that they’ve won a lot of close games. The Heat are the reverse situation so you would figure that they haven’t fared as well in the close ones. In fact, in games decided by 3 points or less, the Spurs are the top team in the NBA with a 73.3% winning percentage and the Heat are third to last with a 31.6% winning percentage.
Offensive and Defensive Ratings and Pace
Traditionally, if you want to evaluate how good a team is on offense or defense, you simply look at how many points that team scores or gives up per game. You might also take a look at the team’s shooting percentages to get a better handle on its offensive performance and its opponents’ shooting percentages for defensive performance.
These remain important team statistics, but they ignore the team’s relative pace of play. Does the team fast break at every opportunity, often getting up a shot in the first 10 seconds of a possession, or are they a halfcourt team that uses just about all of the 24-second clock? Are they an exceptional offensive rebounding team that often creates multiple possessions on offense?
To quantify pace of play, basketball statisticians created the “Pace Factor” statistic that is an estimate of a team’s offensive possessions per 48 minutes. Currently, the fastest-paced team in the NBA is the Minnesota Timberwolves with a 96.4 Pace Factor. The slowest paced team is the Portland Trailblazers at 88.2. Interestingly, the Bulls, Lakers, Celtics, Mavericks and Heat, 5 of the top 6 teams in the league, have very similar team Pace factors (between 90.4 and 91.0).
If a team plays at a very fast pace, they can to some extent, afford to have a lower shooting percentage than slower-paced teams. However, fast-paced teams also tend to give their opponents to have additional possessions. The Timberwolves score a very respectable 101.1 points per game, 10th-best in the NBA. However, the T-Wolves’ opponents score 106.8 points per game…worst in the league and the key reason why they are 17-57.
I’ve occasionally given the stats guys a hard time in this series, but I have to tip my hat to them for creating the team Offensive Rating (ORtg) and Defensive Rating (DRtg) statistics. These are both easy to understand and as I see it, are clearly superior to the simple points scored and points allowed per game stats.
ORtg is the number of points a team scores per 100 possessions. As you probably guessed, DRtg is the number of points allowed per 100 possessions. You’ve also probably figured out that the reason these stats are better is that, since the basis is 100 possessions rather than per game, they adjust for pace of play. They also adjust for teams that happen to play an unusually high number of overtime games.
The top 5 teams in the NBA in terms of ORtg are:
Denver Nuggets – 112.6
Lakers – 111.8
Houston Rockets – 111.6
Spurs – 111.5
Heat – 111.2
Obviously, all are extremely potent offensive teams.
The top-5 for DRtg are:
Bulls – 100.0
Celtics – 100.1
Magic – 102.0
Milwaukee Bucks – 102.6
Heat 103.7
Unlike the top-5 in ORtg which were close bunched, in terms of DRtg, the Bulls and Celtics are clearly the defensive standouts. The Heat stand out in terms of offensive-defensive balance, though the Lakers (7th in DRtg at 104.6) and Spurs (9th in DRtg at 105.2) are also strong on both ends. Of the teams making these top-5s, only the Bucks have a sub-.500 record (they’re next-to-last in ORtg) proof that you can succeed in the NBA by being exceptional on either side of the ball (as long as you’re not godawful on the other side).
For all of the team statistics featured in this article, as well as most of the individual stats used in the earlier installments of this series, go to:
This concludes the stats series. Hope you found it interesting, informative or at least not excessively painful.
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