Quantified Shooter Impact (qSI)

Quantified Shooter Impact (qSI) is metric developed by using Second Spectrum video tracking data. It measures the amount of impact that the player added compared to league average.

After video tracking, we can break down “effective field goal percentage” to “quality of the shot” (toughness of the shot) and the “impact of the shooter” (the ability of a player to finish).

If effective field goal percentage is an overall way to evaluate a shooter, its difference with shot quality (qSQ) explains the quantified shooter impact (qSI).