Visualizing Offensive Style: Year-to-year comparisons

Towards the end of last season, I took a stab at quantifying and visualizing the stylistic tendencies of different NBA offenses. The project built on work by Adam Mares and looked at team offenses across four characteristics — pace, shot selection, ball movement and player movement. The result was rough but offered what was[1. I believe] a helpful snapshot of how teams set up their different offensive systems. For example, we were able to see that efficient offense didn’t necessarily have a specific structure. The two most efficient offenses in the league at that point were the Los Angeles Clippers and the Golden State Warriors, two teams with very different offensive styles.

Now, with a few tweaks, I’ve built team offensive style charts for this season as well. Just like last season, pace is based on the average length of an offensive possession, from Inpredictable. Shot selection is measured by Seth Partnow’s XeFG%. Some new offerings from the NBA’s player tracking statistics now give us better measures for player and ball movement. Player movement is simply offensive distance traveled divided by time of possession. Ball movement is average touch time (with a shorter average touch time indicating more ball movement).

In each case, the outer edges of axis represent more of that characteristic (or generically more efficient in the case of shot selection). With two years of data[2.I actually have three years worth but that’s for another post] to build these charts from we are able to see how some offenses have changed from year to year. For example, we can see how the post play of Jahlil Okafor may be slowing down a Philadelphia 76ers offense that was very similar to the Warriors in style last season.

Year-to-year style charts for all 30 teams are at the bottom of this post[3. If you’re a blogger or writer and want to use one of these images in your work, feel free, just please link back to Nylon Calculus]. You can see the rebuild in Charlotte, the small ball experiment for the Washington Wizards, and what Fred Hoiberg’s system looks like for the Chicago Bulls. We can also, somewhat roughly, quantify and compare the overall change. By the absolute value of change in each of the four categories, the five offenses that have stayed the most stylistically consistent are (in order): the Golden State Warriors, Houston Rockets, Miami Heat, Indiana Pacers and New York Knicks. The five offenses with the highest degree of stylistic change have been (in order): the Milwaukee Bucks, New Orleans Pelicans, Washington Wizards, Detroit Pistons and Chicago Bulls.

Obviously, these charts aren’t capturing everything about how a team’s offense functions or all the stylistic components contained within. But they’re a nice place to start thinking about what each does and to begin asking questions about why and how successful they are.