Originally Posted by
hurleyfor3
Here's one flaw with the RPI, at least how I interperet every definition I've seen of it.
Imagine two teams, let's call them Duke and unc. Both teams are undefeated. Unc has played five games; Duke has played six. Five of Duke's six opponents are the same as unc's opponents. Duke's sixth opponent has a W-L and RPI SOS below the average of the other five.
Unc will always be ranked above Duke, solely because the extra team Duke has played draws its average down. More broadly, Duke is punished for having more "trials", even though one could more stongly argue that more wins give supporting evidence that the other wins weren't chance. And this completely ignores venue (home/road/neutral), margin of victory or how recently the games were played.
Or put another way, I'm more impressed with a team that has beaten #2, #3, #201 and #202 than a team that has beaten numbers 99, 100, 101 and 102. Talent in college basketball is nonlinearly distributed (there's always a bigger difference between #1 and #20 than between 201 and 220), but I'm not sure the RPI accounts for this. This, I think, is one way teams can game the system.