Effective Field Goal Percentage (or eFG%): Shooting percentage from the floor which accounts for the extra point coming from made 3-point baskets.
The formula is (Field Goals Made + 0.5 * 3-Point FGM) / Field Goal Attempts
Net Points: Evaluates scoring production while accounting for shooting efficiency.
The formula is Points - True Shot Attempts
Points Above Average: Number of points scored compared to league average given a specific number of shot attempts.
The formula is Points - (True Shot Attempts * League Avg. Points/TSA)
Rebound Percentage: Rebounds divided by rebounding chances.
The formula for teams is Team Rebounds/(Team Rebounds + Opponent Rebounds)
Replacement Level: For shooting efficiency we estimate replacement level at 90% of league average (90 True Shooting+). Teams that have shot ~10% worse than average have won around 25% of their games over NBA history. Think the 2016 Lakers or the 76ers from 2015.
True Shot Attempts: An estimate of a players total shot attempts used. In addition to shots from the floor every two free throw attempts count as almost one True Shot.
The formula is Field Goal Attempts + 0.44 * Free Throw Attempts
True Shooting: Actual points scored per 100 True Shot Attempts. No adjustment made for league wide shooting. This is two times True Shooting Percentage.
True Shooting Plus (or TS+): Points scored per 100 True Shot Attempts adjusted for league. Players in poor shooting leagues will have their True Shooting increased while players in good shooting seasons will have their TS decreased. 100 is league average in every NBA season.
True Shooting Minus (or TS-): Points allowed per 100 True Shot Attempts adjusted for league. 100 is league average in every NBA season.
Turnover Margin: Team turnovers minus opponent turnovers. Lower is better.