WAB, RPI, Pyth, and Jason Lisk

I’m not sure how many of you have seen this by Jason Lisk:

Comparing Teams Viewed Differently by RPI and Pomeroy Ratings

I’ve been on the Death to the RPI bandwagon for a long time due to what it measures:

RPI = (WP * 0.25) + (OWP * 0.50) + (OOWP * 0.25)

where WP is Winning Percentage, OWP is Opponents’ Winning Percentage and OOWP is Opponents’ Opponents’ Winning Percentage.

https://en.wikipedia.org/wiki/Rating_Percentage_Index#Basketball_formula

“The RPI formula also has many flaws. Due to the heavy weighting of opponents winning percentage, beating a team with a bad RPI may actually hurt your RPI. In addition, losing to a good RPI team can help your RPI. That’s right, LOSING games against good teams may help your RPI.”

The above sin could be pardoned if we took MoV into account, but not as RPI is currently calculated. RPI is 75% a (poor) measure of strength of schedule. That inherently favors teams with scheduling power and hurts teams without it. That is also why RPI is the de facto measuring stick the committee uses (although not directly). You’ll hear a lot about records vs. various sections of the RPI (3-3 vs. the top 50, 7-4 vs. the top 100, etc). That is generally how RPI is used, and it’s still a complete disaster.

The Kenpom ratings that Jason is referring to are the Pythagorean ratings. Those tell you how well (or poorly) teams have performed over every possession they’ve played throughout the season.

http://kenpom.com/blog/index.php/weblog/entry/ratings_glossary

So if RPI measures SoS, and Pyth measures how well a team has played overall, what is then is the point of WAB and Percentile? The answer in a single word is: Resume. I want to measure how good each team’s “Body of work” is:

http://www.ncaa.com/news/basketball-men/article/2012-02-15/qa-jeff-hathaway

Every game counts. The games in December count as much as the games in February.

 

I’d like to focus on Arkansas-Little Rock for a moment. They’re 58th in the RPI and have the 44th best Pyth rating, but neither of those is a measure of resume. If you were to put an average bubble quality squad through Arkansas-Little Rock’s schedule so far, they’d average 15 wins. At 17-2 Arkansas-Little Rock has earned their way into the 24th spot in the WAB rankings. Grand Canyon is also performing very well against their schedule, coming in at 36th in WAB. They’re 93rd in the RPI, and have the 85th best Pyth rating.

There is a psychological bias against rewarding teams for winning games they are expected to win, as well as a bias against punishing teams for losing games they are expected to lose. There is an opposing bias as well, punishing teams for losing games they are expected to win (bad losses), and rewarding teams for unexpected victories (good wins).  If a bubble team goes 9-1 in ten games where they’d have an average expected win percentage of 80%, is the net effective result simply one bad loss? If so, then the process is both biased and absurd. WAB is neither:

Rank School WAB Bubble Percentile
1 Oklahoma 5.97 99.95%
2 Villanova 4.60 99.41%
3 Xavier 4.55 99.44%
4 North Carolina 4.51 99.30%
5 Iowa 4.04 98.92%
6 West Virginia 3.78 98.10%
7 Iowa St. 3.64 97.39%
8 SMU 3.54 98.39%
9 Texas A&M 3.48 96.56%
10 Kansas 3.44 96.97%
11 Virginia 3.40 95.93%
12 Michigan St. 3.20 95.57%
13 Maryland 3.07 96.35%
14 Miami FL 3.01 94.78%
15 Providence 2.83 94.47%
16 South Carolina 2.73 94.27%
17 Dayton 2.69 93.46%
18 Baylor 2.68 94.39%
19 Purdue 2.58 91.68%
20 Louisville 2.47 92.76%
21 Utah 2.31 88.51%
22 Oregon 2.28 88.08%
23 Kentucky 2.09 87.06%
24 Arkansas Little Rock 2.00 89.55%
25 Saint Joseph’s 1.89 85.67%
26 Arizona 1.89 85.03%
27 Michigan 1.64 82.63%
28 USC 1.62 80.23%
29 Pittsburgh 1.30 77.54%
30 Indiana 1.25 74.73%
31 Valparaiso 1.18 73.74%
32 Saint Mary’s 1.12 75.55%
33 Chattanooga 1.05 73.70%
34 Duke 1.03 69.28%
35 Colorado 1.00 69.65%
36 Grand Canyon 0.94 74.14%
37 Notre Dame 0.85 68.46%
38 Texas 0.84 66.18%
39 Butler 0.67 64.47%
40 Florida St. 0.66 64.14%
41 George Washington 0.60 62.30%
42 Monmouth 0.57 61.49%
43 Hawaii 0.55 64.40%
44 Evansville 0.54 61.62%
45 UC Irvine 0.52 60.91%
46 Wichita St. 0.51 60.31%
47 Connecticut 0.45 59.54%
48 Florida 0.39 57.66%
49 VCU 0.29 55.49%
50 Seton Hall 0.28 55.73%
51 Texas A&M Corpus Chris 0.24 55.66%
52 Akron 0.19 53.17%
53 Gonzaga 0.08 50.70%
54 Southern Illinois -0.03 46.97%
55 Cincinnati -0.04 48.37%
56 Texas Tech -0.16 46.03%
57 Princeton -0.18 43.94%
58 UAB -0.27 41.02%
59 California -0.33 42.55%
60 UCLA -0.38 42.05%
61 Kansas St. -0.41 40.59%
62 Boise St. -0.41 40.11%
63 Stony Brook -0.42 37.78%
64 Northwestern -0.43 39.28%
65 Clemson -0.44 40.00%
66 San Diego St. -0.57 36.95%
67 UT Arlington -0.57 34.35%
68 Syracuse -0.58 37.34%
69 Washington -0.61 35.98%
70 Oregon St. -0.66 34.94%
71 Georgetown -0.78 33.70%
72 James Madison -0.78 30.91%
73 Vanderbilt -0.80 33.15%
74 Georgia Tech -0.81 32.93%
75 Creighton -0.82 31.82%
76 South Dakota St. -0.84 30.63%
77 LSU -0.87 31.38%
78 Alabama -0.95 30.78%
79 North Florida -1.00 25.98%
80 Tulsa -1.02 29.35%
81 Hofstra -1.03 27.96%
82 IPFW -1.03 26.47%
83 Northern Illinois -1.04 23.67%
84 Belmont -1.07 26.28%
85 Stanford -1.13 26.89%
86 Marquette -1.18 24.42%
87 Davidson -1.20 22.79%
88 Kent St. -1.21 22.10%
89 Middle Tennessee -1.28 21.67%
90 Yale -1.29 17.03%
91 BYU -1.35 22.60%
92 William & Mary -1.38 19.96%
93 Houston -1.50 17.93%
94 Wisconsin -1.50 21.53%
95 Wake Forest -1.50 22.08%
96 Georgia -1.52 20.05%
97 St. Bonaventure -1.59 17.51%
98 Ohio St. -1.64 16.97%
99 Temple -1.65 18.45%
100 Arizona St. -1.70 18.85%
101 Mississippi -1.88 14.77%
102 Louisiana Tech -1.96 9.91%
103 UNC Wilmington -1.98 10.62%
104 Virginia Tech -1.98 13.60%
105 Fresno St. -2.00 11.79%
106 Georgia St. -2.01 9.39%
107 Stephen F. Austin -2.12 6.40%
108 Nebraska -2.26 9.71%
109 UNLV -2.33 9.88%
110 Mercer -2.35 7.66%
111 Memphis -2.38 7.14%
112 Duquesne -2.42 8.04%
113 Albany -2.49 5.78%
114 Oakland -2.52 7.94%
115 Siena -2.52 7.78%
116 Tennessee St. -2.53 4.39%
117 Pepperdine -2.57 7.62%
118 East Tennessee St. -2.58 6.05%
119 College of Charleston -2.68 5.80%
120 Richmond -2.72 5.92%
121 Columbia -2.73 3.65%
122 Rhode Island -2.77 6.13%
123 Cal St. Bakersfield -2.82 3.06%
124 Winthrop -2.86 3.30%
125 Navy -2.91 3.59%
126 Milwaukee -2.96 3.92%
127 Tennessee Tech -3.00 3.14%
128 Nebraska Omaha -3.16 3.75%
129 Arkansas -3.17 5.30%
130 Oklahoma St. -3.19 3.89%
131 Illinois -3.19 4.78%
132 Nevada -3.22 3.41%
133 North Carolina St. -3.23 5.27%
134 New Mexico -3.24 3.18%
135 Penn St. -3.28 4.17%
136 Southern -3.34 1.90%
137 Ohio -3.35 2.46%
138 Montana -3.36 1.44%
139 Tennessee -3.36 4.52%
140 Weber St. -3.42 1.56%
141 Utah St. -3.48 2.12%
142 North Dakota St. -3.48 1.91%
143 Elon -3.51 2.62%
144 High Point -3.53 1.43%
145 Auburn -3.54 3.41%
146 Indiana St. -3.55 2.97%
147 Towson -3.55 1.77%
148 Green Bay -3.57 2.11%
149 Northeastern -3.60 2.91%
150 Wright St. -3.61 1.59%
151 Buffalo -3.62 1.91%
152 Louisiana Lafayette -3.70 0.93%
153 New Mexico St. -3.74 1.45%
154 UNC Asheville -3.85 1.33%
155 Ball St. -3.87 0.95%
156 Houston Baptist -3.88 0.54%
157 Bowling Green -3.96 0.89%
158 Vermont -4.11 1.02%
159 Fordham -4.14 0.35%
160 UCF -4.16 0.67%
161 UC Santa Barbara -4.27 1.27%
162 Long Beach St. -4.36 1.35%
163 TCU -4.46 0.68%
164 Hampton -4.47 0.21%
165 Wagner -4.50 0.11%
166 Colorado St. -4.57 0.39%
167 Radford -4.57 0.59%
168 Cal Poly -4.62 0.27%
169 Idaho -4.66 0.34%
170 Marshall -4.74 0.49%
171 Illinois St. -4.74 0.53%
172 Harvard -4.74 0.14%
173 Toledo -4.77 0.38%
174 Iona -4.78 0.29%
175 Northern Iowa -4.79 0.67%
176 Fairfield -4.82 0.32%
177 Incarnate Word -4.84 0.01%
178 Washington St. -4.84 0.31%
179 Coastal Carolina -4.87 0.18%
180 Oral Roberts -4.90 0.55%
181 Mississippi St. -4.91 0.25%
182 Eastern Michigan -4.91 0.24%
183 Texas St. -4.95 0.04%
184 East Carolina -4.97 0.46%
185 Central Michigan -5.06 0.21%
186 Cornell -5.19 0.09%
187 Morehead St. -5.19 0.13%
188 Missouri -5.23 0.18%
189 Loyola Marymount -5.34 0.14%
190 Army -5.37 0.05%
191 Old Dominion -5.38 0.12%
192 Western Kentucky -5.52 0.07%
193 Texas Southern -5.58 0.05%
194 Detroit -5.63 0.07%
195 Florida Gulf Coast -5.63 0.03%
196 San Francisco -5.65 0.03%
197 Saint Peter’s -5.65 0.03%
198 New Hampshire -5.66 0.02%
199 Murray St. -5.70 0.13%
200 Bucknell -5.80 0.05%
201 DePaul -5.82 0.19%
202 South Dakota -6.06 0.10%
203 Massachusetts -6.08 0.05%
204 Arkansas St. -6.09 0.02%
205 Samford -6.11 0.01%
206 Sam Houston St. -6.12 0.01%
207 North Dakota -6.13 0.01%
208 Penn -6.17 0.00%
209 FIU -6.17 0.01%
210 UTEP -6.19 0.01%
211 Furman -6.20 0.02%
212 Dartmouth -6.24 0.00%
213 Jackson St. -6.27 0.00%
214 Saint Louis -6.47 0.03%
215 IUPUI -6.50 0.05%
216 Sacramento St. -6.52 0.00%
217 Manhattan -6.54 0.01%
218 Colgate -6.55 0.01%
219 NJIT -6.58 0.01%
220 Howard -6.65 0.00%
221 Louisiana Monroe -6.69 0.01%
222 South Carolina St. -6.73 0.01%
223 Boston College -6.74 0.01%
224 Air Force -6.77 0.01%
225 Utah Valley -6.79 0.00%
226 St. Francis PA -6.84 0.00%
227 Wofford -6.87 0.00%
228 Eastern Washington -6.90 0.00%
229 Fairleigh Dickinson -6.92 0.00%
230 Western Illinois -6.95 0.00%
231 Eastern Kentucky -6.99 0.00%
232 Loyola Chicago -7.00 0.00%
233 Denver -7.02 0.01%
234 Gardner Webb -7.03 0.00%
235 Western Carolina -7.06 0.00%
236 Tennessee Martin -7.07 0.00%
237 Canisius -7.07 0.01%
238 Idaho St. -7.08 0.00%
239 Wyoming -7.09 0.02%
240 Northern Kentucky -7.18 0.00%
241 UC Davis -7.25 0.00%
242 Jacksonville -7.27 0.00%
243 Norfolk St. -7.28 0.00%
244 Portland St. -7.35 0.00%
245 Brown -7.37 0.00%
246 Montana St. -7.44 0.00%
247 McNeese St. -7.46 0.00%
248 George Mason -7.49 0.01%
249 Alabama A&M -7.51 0.00%
250 Tulane -7.60 0.00%
251 Mount St. Mary’s -7.61 0.00%
252 Georgia Southern -7.62 0.00%
253 South Alabama -7.63 0.00%
254 Youngstown St. -7.64 0.00%
255 Western Michigan -7.67 0.00%
256 Missouri St. -7.67 0.00%
257 Savannah St. -7.70 0.00%
258 St. John’s -7.73 0.00%
259 Cal St. Fullerton -7.82 0.00%
260 Boston University -7.83 0.00%
261 Rutgers -7.87 0.00%
262 Alcorn St. -7.90 0.00%
263 UC Riverside -7.93 0.00%
264 LIU Brooklyn -7.95 0.00%
265 UMKC -7.96 0.00%
266 Lamar -8.02 0.00%
267 La Salle -8.04 0.00%
268 The Citadel -8.24 0.00%
269 Charleston Southern -8.26 0.00%
270 Charlotte -8.33 0.00%
271 Seattle -8.41 0.00%
272 Minnesota -8.47 0.00%
273 Pacific -8.49 0.00%
274 VMI -8.56 0.00%
275 Presbyterian -8.61 0.00%
276 Coppin St. -8.64 0.00%
277 Portland -8.64 0.00%
278 San Diego -8.65 0.00%
279 Eastern Illinois -8.68 0.00%
280 Lehigh -8.69 0.00%
281 New Orleans -8.77 0.00%
282 Holy Cross -8.86 0.00%
283 Appalachian St. -8.87 0.00%
284 Delaware -8.88 0.00%
285 Rider -8.93 0.00%
286 UNC Greensboro -8.99 0.00%
287 Southern Miss -9.14 0.00%
288 Southern Utah -9.16 0.00%
289 Abilene Christian -9.21 0.00%
290 Grambling St. -9.23 0.00%
291 Austin Peay -9.23 0.00%
292 Bryant -9.23 0.00%
293 North Texas -9.28 0.00%
294 Cleveland St. -9.30 0.00%
295 Alabama St. -9.30 0.00%
296 Central Arkansas -9.31 0.00%
297 Santa Clara -9.34 0.00%
298 Quinnipiac -9.36 0.00%
299 Campbell -9.42 0.00%
300 Miami OH -9.46 0.00%
301 Kennesaw St. -9.63 0.00%
302 Northern Colorado -9.65 0.00%
303 Cal St. Northridge -9.70 0.00%
304 UMass Lowell -9.77 0.00%
305 Maine -9.87 0.00%
306 St. Francis NY -9.91 0.00%
307 Loyola MD -9.94 0.00%
308 Stetson -10.05 0.00%
309 Maryland Eastern Shore -10.22 0.00%
310 Troy -10.25 0.00%
311 Florida Atlantic -10.27 0.00%
312 Rice -10.28 0.00%
313 Lafayette -10.29 0.00%
314 Northern Arizona -10.29 0.00%
315 Northwestern St. -10.32 0.00%
316 Arkansas Pine Bluff -10.33 0.00%
317 Florida A&M -10.36 0.00%
318 Nicholls St. -10.37 0.00%
319 Drexel -10.77 0.00%
320 Liberty -10.78 0.00%
321 Marist -10.83 0.00%
322 Bethune Cookman -10.83 0.00%
323 South Florida -10.84 0.00%
324 Drake -10.86 0.00%
325 American -10.93 0.00%
326 UT Rio Grande Valley -10.94 0.00%
327 SIU Edwardsville -10.96 0.00%
328 North Carolina Central -10.97 0.00%
329 Southeastern Louisiana -11.11 0.00%
330 Sacred Heart -11.16 0.00%
331 Jacksonville St. -11.17 0.00%
332 Robert Morris -11.19 0.00%
333 Binghamton -11.24 0.00%
334 Morgan St. -11.27 0.00%
335 Hartford -11.35 0.00%
336 Lipscomb -11.44 0.00%
337 San Jose St. -11.49 0.00%
338 Niagara -11.70 0.00%
339 Southeast Missouri St. -11.79 0.00%
340 Bradley -12.02 0.00%
341 UTSA -12.11 0.00%
342 USC Upstate -12.21 0.00%
343 Delaware St. -12.41 0.00%
344 Longwood -12.63 0.00%
345 Mississippi Valley St. -12.69 0.00%
346 Prairie View A&M -12.70 0.00%
347 North Carolina A&T -13.07 0.00%
348 Illinois Chicago -13.22 0.00%
349 UMBC -13.24 0.00%
350 Chicago St. -13.73 0.00%
351 Central Connecticut -15.54 0.00%
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