Commentary and Theory with a yinzer slant #year9

Pittsburgh RPI Ratings are a Mess

Don’t bother taking these seriously.

In case you’re not familiar, RPI is defined as such:

RPI (ratings percentage index) is a rating that applies to a team’s record and schedule such that the stronger the opponents, the higher the RPI rating. Conversely, the weaker the opponents, the lower the RPI rating. In order to tabulate an RPI rating, each opponent’s strength has to be evaluated by examining its W-L record as well as the W-L record of its opponents.

RPI = (1/4 * team’s record) + (1/2 * opponents’ record) + (1/4 * opponents’ opponents’ record)

Records are in the usual form of a win proportion: wins / (wins + losses). Ties are treated as 1/2 win + 1/2 loss. Here is an example of the computation:

A team has played 8 of its 12 games through the season. The team’s record is 7 wins and 1 loss or 0.875.

1 Pine Richland       1  0.8724   36   0     34   0    2  1  0  1  0  0  0  0  0  1  1  0
   2 Seneca Valley       2  0.7903   38   0     37   0    5  1  0  2  1  0  0  0  0  3  0  0
   3 Sewickley Academy   3  0.7604   40   0     39   0    1  2  0  1  1  0  0  0  0  0  1  0
   4 North Allegheny     4  0.6625   30   0      5   1    2  1  0  2  0  0  0  0  0  0  1  0
   5 Bethel Park         5  0.6120    9   0      8   0    3  1  0  2  1  0  0  0  0  1  0  0
   6 Mount Lebanon       6  0.6112    4   1     29   0    3  0  0  2  0  0  0  0  0  1  0  0
   7 Moon Area           7  0.5897   28   0      4   1    5  1  0  3  0  0  0  0  0  2  1  0
   8 Fox Chapel          8  0.5844   18   0     17   0    3  1  0  1  0  0  0  0  0  2  1  0
   9 Greensburg Cath Ce  9  0.5750   21   0      3   1    0  1  0  0  0  0  0  0  0  0  1  0
  10 Mars Area          10  0.5701    1   2     27   0    4  0  0  3  0  0  0  0  0  1  0  0
  11 Peters Township    11  0.5628   35   0     33   0    3  1  0  2  0  0  0  0  0  1  1  0
  12 Hampton            12  0.5524   22   0     21   0    3  1  0  2  0  0  0  0  0  1  1  0
  13 Penn-Trafford      13  0.5381   34   0      7   1    4  3  0  2  3  0  0  0  0  2  0  0
  14 Quaker Valley      14  0.5149    5   1     36   0    2  1  0  0  0  0  0  0  0  2  1  0
  15 Shaler Area        15  0.5148   42   0     41   0    1  5  0  1  2  0  0  0  0  0  3  0
  16 North Catholic-Wue 16  0.5146   31   0     31   0    2  0  0  1  0  0  0  0  0  1  0  0
  17 Upper St Clair     17  0.5021   45   0     45   0    2  1  0  1  0  0  0  0  0  1  1  0
  18 Aquinas Academy    18  0.5000    7   0      1   1    0  1  0  0  0  0  0  0  0  0  1  0
  19 Norwin             19  0.5000   33   0      6   1    0  1  0  0  0  0  0  0  0  0  1  0
  20 Central Catholic   20  0.4913   12   0     11   0    1  2  0  0  1  0  0  0  0  1  1  0

Obviously not indicative of the actual top 10 or top 20 teams but always fun to get worked up over LaxPower.

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