Tue Mar 08, 2011 7:10 pm
This great new data is from Stats, LLC, as they have added multiple cameras (hence the optical in the title) to 3 NBA courts, with the sole intention of recording everything that occurs on the court. Players are tracked, with an exact location in x,y coordinates, as are referees and the ball. 25 times a second, software analyzes the video, and stores information about where everyone is and what is occurring. 1,000,000 entries per game with 60 some games added to their databases so far. Basic things like field goal attempts, blocks, rebounds, and assists are part of what is tracked. And that’s where it starts getting really cool – player position and defender proximity to a player are now available without having to chart and track a game by hand and eyeball estimates.
For his hot hand research, Sandy relied on play by play data to generate possession and play data on a granular level – but with the limitations inherent to play by plays. Passes aren’t tracked, unless they end in an assist; who had the ball in their hands during the possession is unavailable; where was the defender when a shot was taken is an unknown. But not anymore.
The focus of Weill’s research this time was on distance – from the rim and from defenders – and the impact on field goal percentage. Stats, LLC’s new tool provides exactly that, as Sandy was able to look at over 6,000 field goal attempts with the knowledge of where the shot was taken and the distance from defenders. Yes, plural defenders, as the range from all defenders is available, giving the ability to recognize double teams and an oncoming defender.
The three primary results of Weill’s poring through the data and accounting for things like historical player shooting percentages, distance, and shot type:
-Tight defense (within three feet) drops expected shooting 12% points (ie – a 50% shot becomes a 38% shot)
-FG% drops 1% point for every 1.5 feet from the rim
-There is something beneficial about the catch and shoot, beyond expectations
Tue Mar 08, 2011 9:13 pm
Tue Mar 08, 2011 9:19 pm
Tue Mar 08, 2011 9:48 pm