Quantified Shot Quality (qSQ)


Quantified Shot Quality (qSQ) is a metric developed by using Second Spectrum video tracking data.

In brief, qSQ is the effective field-goal percentage when;
– the type of the shot,
– location of the shot,
– nearby defenders
have taken into account.

Before video tracking era, effective field goal percentage was the most advanced metric to evaluate a shooter. With video tracking data, ball trajectory and the location of players on the court throughout the game are processed by employing machine learning that leads to better evaluate player performance.

qSQ Second Spectrum Image Credit: Second Spectrum Website

Quantified shot quality is the likelihood of a “field goal attempt” turns out to be a “field goal made” after factors such as the velocity of the shooter, the closest defender, the next closest defender, position, distance, and others are taken into account. The higher the qSQ, the easier (in terms of distance-being contested or not at the other factors explained) the shoot is. See also Quantified Shooter Impact metric.

Quantified Shot Quality was first presented at the 2014 MIT Sloan Sports Conference.