Number to Know: 15.5%

Oct 9, 2014; Los Angeles, CA, USA; Golden State Warriors guard Klay Thompson (11) drives against Los Angeles Lakers guard Jordan Clarkson (6) during the first half at Staples Center. Mandatory Credit: Richard Mackson-USA TODAY Sports

With the Opening Night just around the corner, Nylon Calculus is previewing the upcoming season by taking you through some of the most important numbers to know, numbers that help tell stories about players, teams and league-wide trends.

Intuitively, we understand basketball is an easier game when it is played collaboratively. Teammates working in unison tend to produce better outcomes than guys trying to do it all themselves. Though some of the very best players can do just fine creating their own shots, this is not the recipe for sustained, quality offense.

New data such as that provided by the SportVU system is beginning to emerge, supporting this long-held intuition. To get right to the point, in 2013-14 there was a 15.5%[1. In an earlier article about the Golden State Warriors, I asserted this gap was closer to 19%. Further investigation reveals that SportVU’s “points created via assist” includes the extra points from assisted “and ones.” Though the numbers in that post are slightly off as a result, the overall thrust is remains unchanged.] gap in Effective Field Goal Percentage between shots which were “potentially assisted” and those which were not.[2. A second caveat is that due to the way SportVU is explicitly tied to the official play-by-play data, this gap is probably mildly overstated in that the tendency for the generously awarded assist operates as sort of a one way ratchet on this analysis. Those shots would never be recorded as “potentially assisted” if not for thee scorekeeping largesse so are only counted on makes, likely leading to a small overestimation in the difference between assisted and unassisted shot making.] Below is a representation of each team’s assisted and unassisted shooting as well as the gap between the two.:

As the chart shows, the gap is in no way uniform across teams. Those squads with smaller gaps appear to fall into two main categories – those with excellent individual shot creation ability like the Miami Heat, Oklahoma City Thunder, Phoenix Suns, and those with mediocre-to-poor shooting ability (Orlando Magic, Indiana Pacers, Memphis Grizzlies). The squads with larger gaps appear to break into those with efficient, though assist-dependent, scorers and teams which simply have bad offenses, whether through poor execution or simple lack of talent. It will be fascinating to watch whether these general categorizations hold as we develop more seasons of this sort of shooting data.

Unfortunately, similar data on individual players is not yet publicly available, though some of the outcomes can probably be intuited by the percentage of each player’s field goals which are assisted. Players such as Serge Ibaka, Klay Thompson and Kevin Martin would be expected to have a wide split in assisted/unassisted split. In fact one of the main criticisms of Thompson has been his relative lack of shot creation ability. If some of what he showed off the bounce in the preseason holds up, his demand for a max contract extension (not to mention the Warriors’ rumored refusal to include Thompson in a deal for Kevin Love) will start to look a lot more reasonable.