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RPI advantages BCS schools? Hardly.

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Some in the national media have made off-handed comments about the RPI advantaging BCS-conference schools, saying fans of schools like Virginia Tech, Alabama and Nebraska are only complaining about the RPI because their teams happen to be ranked lower in the RPI than other NCAA Tournament hopefuls.

Not only are these "experts" wrong, but if you believe that the Pomeroy ratings are a much better tool at gauging teams--as most of them profess to do--then ironically the opposite is actually true. The RPI ratings seem to favor teams that aren't from BCS conferences, relative to more sophisticated tools like Pomeroy. Now of course, Pomeroy is itself not a perfect tool, but it is widely considered to be a much stronger measure, and in fact is often relied upon heavily by many oddsmakers. For these purposes we'll simply use the Pomeroy ratings as a comparison tool.

The following data is based on the Pomeroy ratings of 2/26 per kenpom.com and the RPI ratings of 2/26 per warrennolan.com. The only teams examined are those ranked in the top 100 of the RPI, since those are the only teams for whom the RPI could potentially be relevant when it comes time for the NCAA and NIT selections.

The full data is below the jump, but here are the aggregate results:

BCS conferences non-BCS conferences
RPI top-100 teams 52 48
Average diff. (Pom.-RPI) -7.1 +15.0
Median diff. (Pom.-RPI) -5.0 +15.5
Overrated teams 7 28
Underrated teams 18 5

The first three rows are fairly self-explanatory. An "overrated" team is defined as a team whose RPI ranking is more than 10 spots higher than its Pomeroy ranking, while an "underrated team is defined as a team whose RPI ranking is more than 10 spots lower than its Pomeroy ranking.

Now, of course there are reasons for some of the teams' discrepancies. Let's take two well-known examples in the SEC for instance: Florida and Kentucky. Pomeroy measures teams' possession-by-possession performance against the opponent's relative strength. To overly simplify it, it gives you credit for how you play, while RPI takes nothing into account other than win percentage. Because of the nature of the systems, you would expect teams that win a lot of close games to be "overrated" while teams that lose a lot of close games to be "underrated". That's exactly what you get with Florida (ranked 20 spots higher in RPI after a ridiculous string of close wins) and with Kentucky (ranked 7 spots lower in RPI after a similar string of close losses).

These examples are natural fluctuations based on the differences in the criteria of the two systems. However, given the large sample sizes of both BCS conference teams and non-BCS teams, those differences should balance out, but they don't. BCS conference teams are disproportionately underrated, and non-BCS teams are disproportionately overrated.

Now, this isn't to say the RPI is inherently biased, and it's certainly not to espouse some crazy conspiracy theory that the NCAA is out to get the BCS schools (though that would would be rich with irony). It is simply to shoot down this baseless allegation that the RPI favors BCS schools, and also highlight which schools and conferences may be getting too much--or too little--credit from the RPI.

BCS Team
Conference
RPI
Pomeroy
Difference
Kansas
Ohio State
Duke
Pitt
Georgetown
Purdue
Texas
Notre Dame
North Carolina
Florida
Wisconsin
St. John's
Arizona
Kentucky
Syracuse
Uconn
West Virginia
Vanderbilt
Louisville
Texas A&M
Kansas State
Tennessee
Villanova
Missouri
Cincinatti
Michigan State
Washington
Illinois
Georgia
UCLA
Boston College
Minnesota
Marquette
Florida State
Penn State
Oklahoma State
Virginia Tech
Clemson
Michigan
Miami
Cal
Ole Miss
USC
Nebraska
Alabama
Maryland
Baylor
Colorado
Washington State
Northwestern
Seton Hall
NC State
Big XII
Big Ten
ACC
Big East
Big East
Big Ten
Big XII
Big East
ACC
SEC
Big Ten
Big East
Pac 10
SEC
Big East
Big East
Big East
SEC
Big East
Big XII
Big XII
SEC
Big East
Big XII
Big East
Big Ten
Pac 10
Big Ten
SEC
Pac 10
ACC
Big Ten
Big East
ACC
Big Ten
Big XII
ACC
ACC
Big Ten
ACC
Pac 10
SEC
Pac 10
Big XII
SEC
ACC
Big XII
Big XII
Pac 10
Big Ten
Big East
ACC
1
2
5
6
7
8
9
10
11
12
13
14
15
16
17
19
20
22
23
27
28
29
30
31
35
36
37
38
39
41
47
49
51
52
53
56
64
65
66
67
71
73
74
75
78
81
83
85
87
98
99
100
3
2
1
6
16
5
4
20
12
32
8
33
17
9
13
27
25
28
15
41
34
46
14
22
21
39
11
23
59
51
70
42
29
43
45
85
31
35
53
62
67
73
47
44
37
19
63
61
55
68
60
82
+2
0
-4
0
+9
-3
-5
+10
+1
+20
-5
+19
+2
-7
-4
+8
+5
+6
-8
+14
+6
+17
-16
-9
-14
+3
-26
-15
+20
+10
+23
-7
-22
-9
-8
+29
-33
-30
-13
-5
-4
0
-27
-31
-41
-62
-20
-24
-32
-30
-39
-18

The "big boys" actually have several overrated teams in the RPI top 30 or so, but the problem comes the rest of the way, particularly in spots 50-100. There are some very badly underrated BCS-conference teams in this range, a big factor since several of them have NCAA aspirations.

Non-BCS Teams Conference RPI Pomeroy Difference
BYU
SDSU
Utah State
George Mason
Xavier
UNLV
Old Dominion
Temple
Memphis
UAB
Southern Miss
Cleveland State
Harvard
Colorado State
Butler
Missouri State
Wichita State
Belmont
Dayton
St. Mary's
VCU
Marshall
Princeton
Drexel
Richmond
Oakland
Gonzaga
UCF
Valparaiso
Charleston
Vermont
Rhode Island
UTEP
Kent State
Bucknell
James Madison
Hofstra
ETSU
Iona
Duquesne
Fairfield
New Mexico
Tulsa
Morehead State
Long Beach State
UW-Milwaukee
Long Island
Portland
MWC
MWC
WAC
Colonial
Atlantic 10
MWC
Colonial
Atlantic 10
CUSA
CUSA
CUSA
Horizon
Ivy
MWC
Horizon
MVC
MVC
A-Sun
Atlantic 10
WCC
Colonial
CUSA
Ivy
Colonial
Atlantic 10
Summit
WCC
CUSA
Horizon
Southern
America East
Atlantic 10
CUSA
MAC
Patriot
Colonial
Colonial
Atlantic Sun
MAAC
Atlantic 10
MAAC
MWC
CUSA
OVC
Big West
Horizon
NEC
WCC
3
4
18
21
24
25
26
32
33
34
40
42
43
44
45
46
48
50
54
55
57
58
59
60
61
62
63
68
69
70
72
76
77
79
80
82
84
86
88
89
90
91
92
93
94
95
96
97
7
10
18
24
38
26
52
36
86
56
65
69
81
64
57
83
54
30
93
48
91
76
96
94
58
74
50
84
103
72
104
118
75
130
95
106
153
108
66
40
88
49
99
111
90
138
129
101
+4
+6
0
+3
+14
+1
+26
+4
+53
+22
+25
+27
+38
+20
+12
+37
+6
-20
+39
-7
+34
+18
+37
+34
-3
+12
-13
+16
+34
+2
+32
+42
-2
+51
+15
+24
+69
+22
-22
-49
-2
-42
+7
+18
-4
+43
+33
+4

A few final notes:

Conference USA is laughably overrated in the RPI. Here are the differences for the five teams in the RPI top 70: +53, +25, +22, +18, +16.

The Horizon League is also getting some friendly RPI numbers. Here are the differences for the three teams in the RPI top 70: +34, +27, +12.

The Mountain West's Big 3 are not badly overrated (+6, +6, +4), but Colorado State (+20) is.

The most laughably overrated league of all has to be the Colonial Athletic Association. Here are the differences for their six top-100 teams: +69, +34, +34, +26, +24, +3.