RPI is not quite as hard as the above link makes it sound.
Basically there are three components – (a) your own adjusted W-L pct (worth 25% of the total); (b) the collective W-L pct of your opponents (worth 50%); and the collective W-L pct of your opponents’ opponents (worth the remaining 25%). So for a basic calculation, first calculate the three components independently:
(A) Your own adjusted W-L pct – This is the most complicated because it is the only one where home court matters – home games carry a weight of 60% and away games carry a weight of 140%. To get a denominator – which is the value of all the games combined – simply multiply each home game by 0.6 and each away game by 1.4. For the numerator, then multiply all home wins by 0.6 and all away wins by 1.4, and add up the sum. Then divide the sum of the wins by the denominator describe above. For Lehigh, the value of the wins is 20 and the value of the losses is 5. Thus LU has an adjusted W-L pct of 20/25 = .80 for the first piece, which gets a 25% weight.
(B) There is no homecourt adjustment for your opponents’ W-L pct. LU’s opponents have a W-L pct of .4343 when each team’s W-L pct is given equal weight. That is the second piece and gets a 50% weight.
(C) LU’s oppnents’ opponents W-L pct is .4838, with each team getting equal weight. That is the third piece and gets 25% weight.
Now the final calculation: .80 x 25% plus .4343 x 50% plus .4838 x 25% = .5381 – which puts LU at 106th in the nation as of this morning.
1. Only D1 games count.
2. Games on neutral courts have a value of 1.0 (as opposed to 0.6 or 1.4).
3. When calculating opponents’ W-L record, omit the game they played with your own team.
- This reply was modified 8 years, 7 months ago by Bison137.