The Herfindahl index, also known as Herfindahl-Hirschman Index or HHI, is a measure of the size of firms in relationship to the industry and an indicator of the amount of competition among them.

The Herfindahl Index can be used to measure scoring balances for NBA teams.

To calculate HHI for each team: (1) divide each player's points scored by the total number of points scored by the team, (2) square that result for each player, (3) sum those squares.