Nylon Calculus 101: The Library
By Seth Partnow
The NBA world is awash with data. Traditional boxscores; SportVU; Synergy; Play-by-Play and Vantage data sets. Numerous sites[1. including this one!] dedicated to parsing, splitting and recombining this raw data into new and interesting statistical measures. With this wealth of information comes a problem typical of our data heavy world. Namely, how does one find that one tidbit one was looking for? To help with that, we at The Nylon Calculus are debuting a new resource called “The Library[1. Mostly because we’re all about academic-sounding wordplay.].”
In The Library, we’ll answer common statistical questions, especially of the “where do I find stat X?” variety. The initial list is not intended to be all-inclusive of possible questions or resources, as much like any FAQ, the Frequency at which Questions are Asked will determine the answers. So please shoot us these sorts of inquiries on twitter with the hashtag #NylonStatsFAQ or send an emal to TheNylonCalculus at Gmail dot com. Below are the first few questions along with some annotations. Additionally, since the answers to many “where do I find?” questions is hopefully “right here on Nylon Calculus,” we’ll have a post running down what you can find in “Our Stats” on Monday.
On to the first batch of questions.
I see a lot of references to how players shoot on passes to or from various teammates. Where can I find this?
To and from passing stats are tracked via SportVU. For example, he are some of rookie Emmanuel Mudiay’s to and from passing stats through November 19:
At present NBA.com does not have these stats collated in one place[4. Stats such as this are readily attainable via some relatively simple web-scraping, though we make it a semi-official policy at Nylon Calculus to not repost or regurgitate NBA.com data without added analysis. At some point in the future as we develop our own improved passing metrics, the full NBA.com data set will be integrated into those numbers.], so searching through individual player pages are the best way to access this data. There are two ways to get there – the first is clicking on a player’s name on the
or via the “Tracking” tab on an individual player stats page:
Are there game logs that include assist chances? Can’t find them on NBA.com.
Potential Assists aren’t (yet?) a part of the Player Tracking Box Score. However, with the addition of date filters to the player tracking pages, you can more or less create your own, even if it is a little bit cumbersome. As a quick example, here you can see the potential assists generated by Oklahoma City in their last game:
If only Russell Westbrook was a real point guard…
Where can I find a team’s strength of schedule and/or SOS adjusted Offensive and Defensive Ratings?
Basketball Reference has both of these – here’s schedule strength and adjusted, O, D and Net Ratings.
How can I find which player is guarding/contesting (if any) a given shot attempt?
SportVU shotlogs show both the closest defender and the distance (center mass to center mass) between shooter and that defender. They are most readily accessible on individual player pages:
Note this is not exactly the same things as “contesting” a shot, as SportVU does not track hand position. Nor does merely accounting for the closest defender always tell the whole story, as in many cases secondary help defenders can have a great effect on shot accuracy especially at the rim.
Where can I compare usage between individual players over single and multiple seasons?
The Basketball Reference Player Comparison Finder: Here is Steph Curry so far compared to Michael Jordan’s 7th season:
Oh…
Is there anyway to calculate offensive and defensive ratings on the fly during a game?
Try this advanced stats calculator.
Where can I find efficiency ratings by time left on the shot clock. I.e.: 7 secs or less efficiency?
There are a number of “standard” filters for shot clock time remaining on the “Tracking Shots” tab of NBA. For more specific looks, try the Shot Tracker from NBA Savant – here are the results for three pointers by team with 17 seconds or more remaining on the shot clock.