Digging Into SportVU’s Team Passing Data

Photo by Cary Edmondson-USA TODAY Sports

Photo by Cary Edmondson-USA TODAY Sports

A few months back, we dug into the individual passing data provided by the SportVU cameras in every NBA arena in order to help determine the best passers in the league. Now that the data contains the same information at the team level as well, it’s as good a time as any to go back and look at which teams were the best and more efficient passing squads last season.

Let’s first take a look at the raw data, which will tell us how many passes a team threw and how many of those passes resulted in assist opportunities, and how many of those assist opportunities turned into assists, free throw assists or secondary assists, which when added together we have dubbed “Assists +”.

[table “2708” not found /]

Of course, we can only glean so much from the raw data. Pace obviously factors heavily into the equation here. Teams that play faster have more opportunities to pass, but the more passes a team throws, the slower their games will likely be, because possessions with multiple passes are inherently longer.

Let’s take this opportunity, then, to look at passes per possession and see what kind of interesting information we can glean from that.

[table “2711” not found /]

Most notable is the Spurs, obviously, who were the only team in the top five in passes per possession that played at a pace faster than the league average. The Hawks were the only other team in the top 10 in passes per possession that played above the league average in pace. Of course, Atlanta head coach Mike Budenholzer was Gregg Popovich’s lead assistant for years and modeled his team’s offense after San Antonio’s. This is a decent window into just how good those teams were at moving the ball.

Conversely, the only teams that played slower than the league average pace to rank in the bottom 10 in passes per possession were the Pelicans and the Magic. The Magic ranked second-to-last in the league in offensive efficiency, but the Pelicans were still able to craft a top-13 offense despite not moving the ball around very well.

Meanwhile, the Spurs and Mavericks were the only above-average offensive teams to rank in the top 10 in passes per possession. Five of the bottom 10 teams in passes per possession (Warriors, Thunder, Suns, Pelicans, Rockets) ranked as above-average in offensive efficiency. Interestingly, all seven of those teams reside in the Western Conference.

Using pace as a factor also allows us to adjust the assist opportunities, assists, free throw assists, secondary assists, and Assists + data to see which teams created the most on a per-possession basis.

[table “2712” not found /]

Interestingly. none of these stats had a strong correlation with offensive efficiency (O-Rtg).

Indeed, five of the league’s top 10 in Assist Opportunities Per 100 Possessions were above-average offensive teams and five were below average. The same is true of the bottom 10 teams in Assist Opportunities Per 100 Possessions.

The Spurs surprisingly did not top the league in Secondary Assists Per 100 Possessions. That honor belonged to the Memphis Grizzlies, which makes a weird bit of sense when you consider the spacing problems they had and how that necessitated multiple passes to even manufacture a score. The next three teams on the list, though, are no surprise: the Spurs, Hawks and Clippers. Again the Spurs and Hawks run similarly-styled offenses that place an emphasis on making the extra pass, and the Clippers had the league’s best offense and Chris Paul running the show.

The Spurs, Hawks and Clippers (in that order) show up atop the Assists + Per 100 Possessions leaderboard, which should not be a shock at this point. The bottom 10 in Assists + Per 100 actually contains four above-average offensive teams (Suns, Knicks, Pelicans and Rockets).

The most surprising nugget here is that the Lakers somehow led the league in Assist Opportunities Per 100 Possessions, perhaps owing to Mike D’Antoni’s offensive system. Each of the top three (Lakers, hawks and Bulls) in the stat ranked as a below-average offensive team, though.

All of that data relates to quantity of passes, though, and we should be able to use the SportVU info to determine the quality of passes as well. With that in mind, let’s take a look at the data for what percentage of each team’s passes were turned into assist opportunities, assists, free throw assists, secondary assists and Assists +.

[table “2713” not found /]

No team turned passes into assists more often as a percentage of their passes than the Warriors, who also threw the fewest amount of passes in the league by almost 1,500 passes. The Nuggets, Thunder and Pistons were also in the bottom-five of passes thrown and the top-five of percentage of passes that resulted in an assist. The same is true of all four of those teams when you sort by percentage of passes that turned into an assist opportunity.

When you sort by the percentage of passes that turned into a free throw assist, you see that the Knicks did this so little times that two teams actually doubled their percentage. The Wolves and Nuggets had 1.15 and 1.16 percent of their passes, respectively, turn into free throw assists, while only 0.57 percent of New York’s passes did the same.

The Clippers, Warriors, Grizzlies, Hawks and Spurs — familiar teams all — showed up atop the list in percentage of passes that turned into a secondary assist, and five of the top-10 teams in that stat were also in the top-10 in offensive efficiency. Six of the bottom-eight teams in offensive efficiency also ranked in the bottom-10 of Secondary Assist Percentage.

We can get a little bit further, examining what percentage of assist opportunities turned into assists or Assists +, which gives us a little better idea of the quality of passes (and the shooters who received them).

[table “2714” not found /]

The Suns were the only top-10 offensive team to rank in the bottom third in Converted Assist %, coming in second-to-last to only the Jazz. Meanwhile, each of the top eight teams in the same stat had above-average offensive efficiency. Seven of those eight teams were also in the top-eight of offensive efficiency, the Suns being the only top-eight offense left out, replaced by the Pelicans.

No team turned assist opportunities into Assists + less often than the Knicks, followed not-all-that-closely by the Kings, Magic and Suns. The top four teams in percentage of assist opportunities that turned into Assists + all had top-six offenses, and the Spurs and Clippers each converted over 10 percent more of their assist opportunities into Assists + than did the Knicks.

As with the last time we examined this type of data, there are some flaws here. It would be nice to know where these assist opportunities, assists and Assists + were generated, both in terms of the shot location and where the pass originates, in order to be able to really differentiate the quality. An assist opportunity at the rim is better than one from mid-range, after all. This data isn’t so much conclusive as it is descriptive and just a fun way to mess around with some of the interesting new stuff the NBA is tracking during the offseason.