Just wondering why rankings and RPI can be so different.  I just moved to #22 in Allen DI (first time for me!), but my RPI is 48.  Just curious...

This is a mystery that has been discussed and debated since the beginning of time. The short answer is that the formula for ranking Top 25 and the formula for RPI are very different. The Top 25 formula is weighted heavily toward perceived team strength (# or Srs, overall ratings, etc.) early in the season. As the season progresses it gradually shifts over to W-L record. The RPI is based on the formula used by the NCAA with slight modifications for home/road wins. In general, the TOP 25 is more accurate toward the end of the season.

Off topic but www.kenpom.com had an article earlier this season about the college basketball poll, it's history, and the rankings. To sum it up, the pre-season poll is actually a better predictor of tourney success than the last poll before the tourney.