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.

The home-court advantage is the net effect of several factors that may have an (generally positive) effect on the play of the home team and an (generally negative) effect on the play of the road team.

Possible Sources of Home Court Advantage in Basketball:

• Psychological support of the fans.

• Comfort of being at home, rather than traveling.

• Referees give home teams the benefit of the doubt?

• Teams are familiar with particulars/eccentricities of their home court.

• Different distributions of rest between home and road teams
  

Calculating The Home Court Advantage:
Subtracting one team’s power rating from another can help predicting point diffential between the two teams. Unless the game is being played at a neutral site the "home court advantage" factor needs to be incorporated for more accurately predicting the point differential of a game.

Knowing the distribution of the teams' home and road performances provides predictive information on estimating home court advantage. The probability of a "random point is picked in the home team's point distribution being greater than the random point picked in road team's point distribution" gives an estimate of the home court advantage.