RPI is also the
Ratings Percentage Index formula used as one of the factors by the
NCAA Division I Men's
Basketball Committee to decide
at-large bids for the
Tournament.
Background
RPI was first used in
1981. It is designed to measure the
strength-of-schedule component for each team. The Committee has historically placed a
premium on this criteria, but needed a way to quantify and compare different schools.
Formula
The basic formula is:
This result, itself a
percentage, is called
basic RPI.
Adjustments
Adjustments are made using a
secret system of bonuses and penalties known
only to the
Committee. What is known is that there are bonuses for "
good wins" (beating a team in the top-50
RPI) and penalties for "
bad losses" (losing to a team in the bottom-50
RPI). Other correction factors are used based on location of games, implementation of a difficult
non-conference schedule, and so forth.
Nominal Values
An
RPI of 0.600 or better at the end of the
regular season is considered quite good. For 2002-2003,
Kentucky has the top estimated basic
RPI of 0.6596.