How to Calculate RPI
1. Multiply the team's number of home wins by 0.6, the number of road wins by 1.4 and the number of neutral site wins by 1 then add the three results. For example, if a team had 3 home wins, 2 road wins and 1 neutral site win, you would compute 3 times 0.6 to get 1.8, 2 times 1.4 to get 2.8 and 1 times 1 to get 1. Then you would add 1.8 plus 2.8 plus 1 to get a win total 5.6.
2. Multiply the team's number of road losses by 0.6, the number of home losses by 1.4 and the number of neutral site losses by 1 then add the results. For example, if the team had four home losses and one road losses and one neutral site loss, you would multiply 4 times 1.4 to get 5.6, 1 times 0.6 to get 0.6 and 1 times 1 to get 1. Then you would add 5.6 plus 0.6 plus 1 to get a loss total of 7.2.
3. Add the totals from steps 1 and 2 to get the game total. In this example, you would add 5.6 and 7.2 to get 12.8.
4. Divide the win total by game total to calculate the team's winning percentage. In this example, you would divide 5.6 by 12.8 to find the team's winning percentage equals 0.4378.
5. Compute the winning percentage of each of the opponents the team has played using the steps 1 through 4. When performing the calculation, do not include the opponent's game against the original team. For example, if you are calculating the RPI for team A and team A played teams E, F, G and H, when you calculate team H's winning percentage you would not include the game team H played against team A.
6. Calculate the average of the opponents' winning percentage by adding the winning percentages and dividing by the number of opponents. For example, if the opponents' averages were 0.5, 0.6, 0.7 and 0.8, you would add 0.5 plus 0.6 plus 0.7 plus 0.8 to get 2.6. Then you would divide 2.6 by 4 to get 0.65.
7. Calculate the winning percentage of the opponents' opponents using steps 1 through 5.
8. Calculate the average of the opponents' winning percentage by adding the winning percentages and dividing by the number of opponents. For example, if the opponents' opponents' averages were 0.4, 0.5, 0.6 and 0.7, you would add 0.4 plus 0.5 plus 0.6 plus 0.7 to get 2.2. Then you would divide 2.2 by 4 to get 0.55.
9. Calculate the RPI by multiplying the team's winning percentage by 0.25, the average of the opponents' winning percentages by 0.5 and the average of the opponents' opponents' winning percentages by 0.25 and adding the results. Finishing this example, you would multiply 0.4378 by 0.25, 0.65 by 0.5 and 0.55 by 0.25 to get a total RPI of 0.473445.
Read more: How to Calculate the RPI in Basketball | eHow.com
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