Did you know that 67% of the Houston Rockets' field goal attempts were from beyond the 3-point line in the 2018-2019 season? Traditional methods of measuring field goal percentage fail to separate two-point shots from three pointers. When it comes to analyzing these percentages, it is important to understand the weight of the different shots. We all understand the concept of risk and reward - here's how it plays out in basketball:
Let's assume player Jack only takes two-point shots and hits 6 of 12 (50%) from the field during Wednesday's game. Jack's made 12 points for the team - at 50% field goal percentage as well as a 50% EFG percentage. What is EFG, or effective field goal percentage, you may ask? Here's the simple formula:
Effective Field Goal% = ((Field Goals Made) + 0.5*3PT Field Goals Made)/(Field Goal Attempts)
Another player, John, took 12 shots from the field and only made 5 but because they are all from three-point territory - John generated 15 points during the game. John's shots are more valuable so the traditional field goal percentage fails to capture the additional value generated by these shots. John's FG% seems lower at 42 FG% but the EFG comes out to 62.5%, proving to have had a more efficient game than Jack.
6/12 2pt FG = 12 points, 50 FG% / 50% EFG
5/12 3pt FG = 15 points, 42 FG% / 62.5% EFG
Accounting for the additional value of a three-point shot is the primary reason effective field goal percentage was created and can more accurately describe how well a team can score. At the team level, EFG becomes particularly important as the increasing the ratio of three-point shots to two-point shots can drastically raise a team's EFG. This concept is one of the pillars of the Houston Rockets' "Moreyball" scheme.
This is a metric that has as much value at the team level as at the individual level. A coach can optimize a lineup based on collective EFG or understand which opponent lineups are the most efficient - and adjust the defensive strategy for the match. At the same time, players can easily track their scoring efficiency in order to better understand which field goal attempts give them the best return and play more strategically.
At Pivot, we incorporate the four factors along with the other critical performance metrics, such as Offensive and Defensive Rating, into each analysis to provide a comprehensive look at both team and player performance.