Wednesday, September 20, 2017

Good Data Sources

For those with a high interest in Division I women's soccer, there are some very good data sources.  Here are the ones that are the most valuable:

NCAA Division I Women's Soccer Schedules (presented by All White Kit).  This is a great source and provides instantaneous ratings as new game results are entered into their system.  And, if you navigate around through the system, it has a whole lot more great information.  I've prepared a Manual that describes a lot of the different things the system can do, which are far more than initially appear on the surface.  (The Manual title refers to the system as the NC-Soccer system, which is the original system that Chris Henderson at AWK inherited, but the Manual applies equally to the AWK system.)

NCAA Statistics.  This part of the NCAA's official data collection system.  The linked page (Available Teams) is a list of the teams with Division I women's soccer.  If you click on the Scoreboard tab (next to the Available Teams tab), you will go to the daily scoreboard, from which you can navigate to earlier or future dates.  On the Available Teams page, if you click on a team's name, you will go to a team page with the team's schedule, including results to date, and statistics.  On the team page, if you click on a game score, you will go to the official box score for the game.  If you navigate around using the different links next to Schedule/Results, you can find all sorts of team-related data.

NCAA RPI Archive.  Here, as the season progresses, the NCAA posts various detailed reports that underlie the RPI Rankings it posts weekly on the Division I Women's Soccer page at the NCAA.com website.  You start by using the Query function on the linked page to ask the system for the Soccer, Women's, Current reports and then designate the reports you want to see.  The reports I typically use are Nitty Gritty (data summary for each team), Team Sheets (an individual page for each team with lots of detailed information to be used by the Women's Soccer Committee in making NCAA Tournament seeding and at large selection decisions), and Team Rankings (all games) (with detailed RPI information for each team).  So far this year, the NCAA statistics staff has not published any reports in the Archive, but hopefully they'll start posting them soon.

Monday, September 18, 2017

2017 RPI Ranks 9.18.2017

This is my first actual RPI report for the year.  It has the bare essentials.  If you want a more report with a lot more detail including conference and regional playing pool average ratings, you can go to the RPI for Division I Women's Soccer website and download them from the RPI: This Year's Reports page.  They're in an Excel workbook that's an attachment at the bottom of the page, 2017 ARPI Report 9.18.2017.

For those really interested in the RPI and how it works, it's important to start out knowing that the Women's Soccer Committee really only should be using the RPI at the end of the season immediately before the NCAA Tournament.  The Committee uses it earlier, as it has its bi-weekly meetings, but hopefully the Committee members know that the RPI at the time of those meetings has significant limitations.

Here's a way to think about the RPI at the current stage of the season.  Let's say a team I'm interested in has played 8 games so far and that each of its opponents has played 8 games.  In terms of effective weight in determining a team's rating, the team's winning percentage and their opponents' average winning percentage account for about 90% of the team's rating.  Thus the competition among 64 teams (our team's opponents' opponents) plus 8 teams (our team's opponents) plus 1 team (our team) account for about 90% of our team's ratings.  Those 73 teams are about 25% of all the Division I teams.  So, about 25% of all teams play a significant role in our team's rating and about 75% of all teams don't.  Each team has its own group that contribute to its rating,but essentially there are a bunch of different playing pools and a team's rating reflects only where it fits within its pool.  But, the ratings all are put together as though a team from one pool has a rating that fits properly in relation to the rating of a team from another pool.  This really isn't true, as the pools aren't equal.

As the season shifts from the non-conference competition to the conference competition, the in-conference competition over the weeks does a better and better job of producing ratings of the conference teams that reflect where they really stand in relation to each other.  This feeds back into the system and, to some extent, gets the non-conference pools of teams in a more correct relation to each other.  Does it get them into a truly correct relation to each other?  No.  It would take in the vicinity of a 28 to 30 game season to overcome the unbalanced nature of the non-conference playing pools, whereas the average team plays about 19 games.

If the season were turned around and the conference season preceded the non-conference season, you might see this better.  At the end of the conference season, each conference's teams' ratings would be essentially the same as each other conference teams' ratings.  The non-conference season then would put the different conferences' teams in a more correct relation to each other.  Again, however, there wouldn't be enough games to do get the teams into a truly correct relation to each other.  And in fact, I have run statistical analyses that prove this:  stronger conferences' teams' ratings are not high enough to match with actual game results and weaker conferences' teams' ratings are not low enough.

So, what you're seeing in this week's RPI report, with the conference season just having begun, is the very early stage of corrections to the ratings from the non-conference season.

With that little lecture, here are the ARPI ranks generated from games played through Sunday, September 17:

Team Conference ARPI Rank 2015 BPs NC
SouthCarolinaU SEC 1
Stanford PacTwelve 2
TexasU BigTwelve 3
UCF American 4
NorthCarolinaU ACC 5
Duke ACC 6
Rutgers BigTen 7
Princeton Ivy 8
FloridaU SEC 9
WestVirginiaU BigTwelve 10
TennesseeU SEC 11
Wisconsin BigTen 12
NCState ACC 13
WakeForest ACC 14
LSU SEC 15
WashingtonU PacTwelve 16
Clemson ACC 17
VirginiaU ACC 18
UCLA PacTwelve 19
Cincinnati American 20
NotreDame ACC 21
Purdue BigTen 22
LoyolaMarymount WestCoast 23
StLouis AtlanticTen 24
Penn State BigTen 25
Marquette BigEast 26
Michigan BigTen 27
Pepperdine WestCoast 28
Rice ConferenceUSA 29
MississippiU SEC 30
VirginiaTech ACC 31
Georgetown BigEast 32
Memphis American 33
CaliforniaU PacTwelve 34
KansasU BigTwelve 35
AlabamaU SEC 36
Butler BigEast 37
SMU American 38
UtahU PacTwelve 39
Baylor BigTwelve 40
TexasA&M SEC 41
IndianaU BigTen 42
SantaClara WestCoast 43
WashingtonState PacTwelve 44
Vanderbilt SEC 45
FloridaGulfCoast AtlanticSun 46
MississippiState SEC 47
OhioState BigTen 48
FloridaState ACC 49
LongBeachState BigWest 50
Maryland BigTen 51
MontanaU BigSky 52
NorthwesternU BigTen 53
ColoradoU PacTwelve 54
BostonCollege ACC 55
MurrayState OhioValley 56
MinnesotaU BigTen 57
Oregon PacTwelve 58
CalStateNorthridge BigWest 59
SouthFlorida American 60
EastCarolina American 61
Auburn SEC 62
Monmouth MetroAtlantic 63
NebraskaU BigTen 64
SouthernCalifornia PacTwelve 65
CollegeofCharleston Colonial 66
Drexel Colonial 67
CalStateFullerton BigWest 68
Syracuse ACC 69
Milwaukee Horizon 70
Navy Patriot 71
Gonzaga WestCoast 72
ArizonaU PacTwelve 73
Northeastern Colonial 74
Providence BigEast 75
BYU WestCoast 76
Harvard Ivy 77
StJosephs AtlanticTen 78
GeorgiaU SEC 79
OklahomaState BigTwelve 80
UNLV MountainWest 81
UCIrvine BigWest 82
Charlotte ConferenceUSA 83
NorthFlorida AtlanticSun 84
KentuckyU SEC 85
MichiganState BigTen 86
Colgate Patriot 87
CoastalCarolina SunBelt 88
Yale Ivy 89
Villanova BigEast 90
NewHampshireU AmericaEast 91
You AtlanticTen 92
Louisville ACC 93
SacramentoState BigSky 94
UCSantaBarbara BigWest 95
Houston American 96
SanFrancisco WestCoast 97
Belmont OhioValley 98
ArkansasU SEC 99
UtahState MountainWest 100
TCU BigTwelve 101
NewMexicoU MountainWest 102
UNCWilmington Colonial 103
Pittsburgh ACC 104
Bryant Northeast 105
GeorgiaSouthern SunBelt 106
FresnoState MountainWest 107
IowaU BigTen 108
LoyolaChicago MissouriValley 109
UAB ConferenceUSA 110
William&Mary Colonial 111
NorthernColorado BigSky 112
TexasTech BigTwelve 113
Hofstra Colonial 114
Elon Colonial 115
Brown Ivy 116
Lehigh Patriot 117
Connecticut American 118
Kent State MidAmerican 119
DelawareU Colonial 120
Old Domain ConferenceUSA 121
MiamiFL ACC 122
GeorgeWashington AtlanticTen 123
UALR SunBelt 124
DePaul BigEast 125
StJohns BigEast 126
Lamar Southland 127
AustinPeay OhioValley 128
JamesMadison Colonial 129
Radford BigSouth 130
RhodeIslandU AtlanticTen 131
UNI MissouriValley 132
Furman Southern 133
ArizonaState PacTwelve 134
MissouriU SEC 135
TexasRGV WAC 136
WesternMichigan MidAmerican 137
IndianaState MissouriValley 138
SouthAlabama SunBelt 139
CentralMichigan MidAmerican 140
NorthTexas ConferenceUSA 141
CalPoly BigWest 142
ArkansasState SunBelt 143
Xavier BigEast 144
LaSalle AtlanticTen 145
Dartmouth Ivy 146
IUPUI Horizon 147
KennesawState AtlanticSun 148
Drake MissouriValley 149
Liberty BigSouth 150
Binghamton AmericaEast 151
Boston Patriot 152
Seattle WAC 153
UNCGreensboro Southern 154
Dayton AtlanticTen 155
LouisianaTech ConferenceUSA 156
SanJoseState MountainWest 157
NorthernIllinois MidAmerican 158
Valparaiso MissouriValley 159
WesternKentucky ConferenceUSA 160
PortlandU WestCoast 161
ColoradoCollege MountainWest 162
LouisianaLafayette SunBelt 163
StephenFAustin Southland 164
Stetson AtlanticSun 165
TennesseeTech OhioValley 166
IllinoisState MissouriValley 167
CentralConnecticut Northeast 168
Quinnipiac MetroAtlantic 169
GeorgeMason AtlanticTen 170
SouthDakotaState Summit 171
SIUEdwardsville OhioValley 172
Wyoming MountainWest 173
UNCAsheville BigSouth 174
KansasState BigTwelve 175
Fairfield MetroAtlantic 176
SanDiegoState MountainWest 177
IowaState BigTwelve 178
NewMexicoState WAC 179
Towson Colonial 180
Bucknell Patriot 181
BowlingGreen MidAmerican 182
WrightState Horizon 183
Samford Southern 184
MiddleTennessee ConferenceUSA 185
ClevelandState Horizon 186
IdahoU BigSky 187
OregonState PacTwelve 188
EasternWashington BigSky 189
NorthernKentucky Horizon 190
OklahomaU BigTwelve 191
NorthernArizona BigSky 192
Toledo MidAmerican 193
Cornell Ivy 194
HighPoint BigSouth 195
WesternCarolina Southern 196
StFrancis Northeast 197
MassachusettsU AtlanticTen 198
SoutheastMissouriState OhioValley 199
Columbia Ivy 200
BoiseState MountainWest 201
Lipscomb AtlanticSun 202
ColoradoState MountainWest 203
TexasCorpusChristi Southland 204
Troy SunBelt 205
HawaiiU BigWest 206
Duquesne AtlanticTen 207
Pacific WestCoast 208
UMassLowell AmericaEast 209
FloridaAtlantic ConferenceUSA 210
AirForce MountainWest 211
CalStateBakersfield WAC 212
UTSA ConferenceUSA 213
EasternIllinois OhioValley 214
Longwood BigSouth 215
Tulsa American 216
EasternKentucky OhioValley 217
Richmond AtlanticTen 218
SanDiegoU WestCoast 219
StonyBrook AmericaEast 220
VermontU AmericaEast 221
StMarys WestCoast 222
Mercer Southern 223
TexasState SunBelt 224
MissouriState MissouriValley 225
IllinoisU BigTen 226
Niagara MetroAtlantic 227
UNOmaha Summit 228
SouthernMississippi ConferenceUSA 229
McNeeseState Southland 230
SamHoustonState Southland 231
Denver Summit 232
MississippiValley Southwestern 233
CharlestonSouthern BigSouth 234
EastTennesseeState Southern 235
UCDavis BigWest 236
Lafayette Patriot 237
Temple American 238
Davidson AtlanticTen 239
OhioU MidAmerican 240
EasternMichigan MidAmerican 241
Creighton BigEast 242
UTEP ConferenceUSA 243
Winthrop BigSouth 244
AlcornState Southwestern 245
NJIT AtlanticSun 246
SacredHeart Northeast 247
Siena MetroAtlantic 248
JacksonvilleState OhioValley 249
utahvalley WAC 250
Army Patriot 251
IncarnateWord Southland 252
Buffalo MidAmerican 253
MaineU AmericaEast 254
SouthDakotaU Summit 255
Presbyterian BigSouth 256
FIU ConferenceUSA 257
Manhattan MetroAtlantic 258
BallState MidAmerican 259
CentralArkansas Southland 260
Chattanooga Southern 261
Canisius MetroAtlantic 262
USCUpstate AtlanticSun 263
Wofford Southern 264
Detroit Horizon 265
Akron MidAmerican 266
PennsylvaniaU Ivy 267
TennesseeMartin OhioValley 268
Marist MetroAtlantic 269
Citadel Southern 270
TexasSouthern Southwestern 271
MKC WAC 272
Marshall ConferenceUSA 273
SouthernUtah BigSky 274
NorthDakotaU BigSky 275
FairleighDickinson Northeast 276
UCRiverside BigWest 277
GrandCanyon WAC 278
Campbell BigSouth 279
MountStMary Northeast 280
HolyCross Patriot 281
JacksonvilleU AtlanticSun 282
NorthwesternState Southland 283
Fordham AtlanticTen 284
Evansville MissouriValley 285
AbileneChristian Southland 286
LongIsland Northeast 287
GeorgiaState SunBelt 288
OralRoberts Summit 289
AlabamaState Southwestern 290
Albany AmericaEast 291
Morehead OhioValley 292
GardnerWebb BigSouth 293
AppalachianState SunBelt 294
Weber State BigSky 295
IdahoState BigSky 296
RobertMorris Northeast 297
American Patriot 298
UMBC AmericaEast 299
Howard Southwestern 300
Wagner Northeast 301
LoyolaMD Patriot 302
YoungstownState Horizon 303
StBonaventure AtlanticTen 304
Grambling Southwestern 305
NorthDakotaState Summit 306
Oakland Horizon 307
MiamiOH MidAmerican 308
Hartford AmericaEast 309
SetonHall BigEast 310
HoustonBaptist Southland 311
IllinoisChicago Horizon 312
VMI Southern 313
PrairieViewA&M Southwestern 314
WesternIllinois Summit 315
Iona MetroAtlantic 316
PortlandState BigSky 317
ArkansasPineBluff Southwestern 318
LouisianaMonroe SunBelt 319
Rider MetroAtlantic 320
NichollsState Southland 321
GreenBay Horizon 322
IPFW Summit 323
NevadaU MountainWest 324
DelawareState Independent 325
StPeters MetroAtlantic 326
SouthCarolinaState Independent 327
SELouisiana Southland 328
SouthernU Southwestern 329
JacksonState Southwestern 330
AlabamaA&M Southwestern 331
Hampton Independent 332
ChicagoState WAC 333