How Accurate Are the Ratings?

Predicting each of Fall 2024, Spring 2025, Fall 2025 and Spring 2026 using only races sailed before that season began, the site's rating model put 69.5% of boat pairs in the right order across 1,356,317 pairs in 15,965 races. The strongest baseline, Elo (multi-player, tuned K), managed 68.0%; a coin flip gets 50%.

Boat pairs ordered correctly
69.5%
+1.5 pts vs Elo
Race winner picked
35%
coin flip picks 11%
Pairwise log-loss
0.582
-1.1% vs Elo · lower is better
Returning sailors only
72.0%
pairs with a newcomer: 62.4%

The question

A rating is only useful if it predicts results it has not seen. The ratings on this site come from a Plackett–Luce model: every skipper has a strength, and a race finish is modelled as repeatedly choosing the next boat across the line with probability proportional to strength. The site's version lets each sailor's strength drift week to week. This page tests whether that model forecasts future races better than simpler ways of rating sailors.

How the test works

  • Strictly forward. For each forecast season, every model is fit only on races from weeks before the season's first race. Ratings are then frozen and used to predict every race of the season. There is no updating during the season, so this is harder than the model's real use on the site.
  • Six models. A coin flip; each sailor's average finish percentile; multi-player Elo; Plackett–Luce with one fixed rating per sailor; the site model before the rating fix, which stopped fitting before its ratings had settled; and the current weekly Plackett–Luce site model.
  • Fair tuning. Baseline settings (Elo's K, average-finish shrinkage, the static model's regularisation, and a probability scale for Elo and average finish) are chosen on the season just before each forecast, using only data from before that season.
  • Newcomers. Sailors with no earlier races get, in every model, the median rating that model gave sailors who debuted the season before.
  • Scoring. Every pair of boats in a race counts once: accuracy is the share ordered correctly, log-loss penalises confident mistakes. Winner picked asks whether the highest-rated boat won; rank correlation compares the predicted order with the finish order. Boats that did not finish are left out of every comparison.

Results

Share of boat pairs ordered correctly, Fall 2024, Spring 2025, Fall 2025 and Spring 2026 pooled
50%55%60%65%70%75%No information (coin flip): 50.0%Coin flip50.0%Average finish percentile: 64.7%Average finish64.7%Elo (multi-player, tuned K): 68.0%Elo68.0%Plackett–Luce, static rating: 68.0%Static PL68.0%Plackett–Luce, weekly, before the rating fix (previous site model): 68.8%Previous site model68.8%Plackett–Luce, weekly (site model): 69.5%Weekly PL (site)69.5%
50%55%60%65%70%75%No information (coin flip): 50.0%Coin flip50.0%Average finish percentile: 64.7%Average finish64.7%Elo (multi-player, tuned K): 68.0%Elo68.0%Plackett–Luce, static rating: 68.0%Static PL68.0%Plackett–Luce, weekly, before the rating fix (previous site model): 68.8%Previous site model68.8%Plackett–Luce, weekly (site model): 69.5%Weekly PL (site)69.5%
Pairwise log-loss (lower is better; a coin flip scores 0.693)
0.550.600.650.70No information (coin flip): 0.693Coin flip0.693Average finish percentile: 0.621Average finish0.621Elo (multi-player, tuned K): 0.589Elo0.589Plackett–Luce, static rating: 0.589Static PL0.589Plackett–Luce, weekly, before the rating fix (previous site model): 0.579Previous site model0.579Plackett–Luce, weekly (site model): 0.582Weekly PL (site)0.582
0.550.600.650.70No information (coin flip): 0.693Coin flip0.693Average finish percentile: 0.621Average finish0.621Elo (multi-player, tuned K): 0.589Elo0.589Plackett–Luce, static rating: 0.589Static PL0.589Plackett–Luce, weekly, before the rating fix (previous site model): 0.579Previous site model0.579Plackett–Luce, weekly (site model): 0.582Weekly PL (site)0.582
ModelPairwise
accuracy
Log-lossWinner
picked
Rank
correlation
ICSA
accuracy
ISSA
accuracy
Returning
sailors
With a
newcomer
No information (coin flip)50.0%0.693210.8%0.00050.0%50.0%50.0%50.0%
Average finish percentile64.7%0.621228.5%0.38565.8%63.8%66.5%59.7%
Elo (multi-player, tuned K)68.0%0.588532.8%0.46169.4%66.8%70.3%61.6%
Plackett–Luce, static rating68.0%0.588932.9%0.45869.6%66.5%70.6%60.5%
Plackett–Luce, weekly, before the rating fix (previous site model)68.8%0.578834.0%0.48170.1%67.7%71.3%61.9%
Plackett–Luce, weekly (site model)69.5%0.581834.6%0.49870.7%68.5%72.0%62.4%

The rating fix. Until September 2026 the model stopped fitting after 2,000 steps, long before the ratings had settled, which squeezed them together. Ratings are now fitted until they settle, with a pull toward the average on each sailor's rating when they start racing, which matters most for sailors with few races; its strength and the week-to-week smoothing were tuned on week-ahead forecasts from 2024 and spring 2025. On these season-ahead forecasts, pairwise accuracy went from 68.8% before the fix to 69.5%, and log-loss from 0.579 to 0.582. Sharper ratings age, though: a whole season ahead they order boats better but state their confidence a little too strongly, which is why log-loss here went the other way. With ratings from the week before an event, which is how the site uses them, they are better on both counts: log-loss 0.547 before the fix against 0.538 now. At championships, with ratings from the week before, the fix was worth +0.3 to +0.7 points of pairwise accuracy (95% interval).

Season by season

Pairwise accuracy for each forecast season. Fall seasons bring a new freshman class, so a larger share of pairs involve sailors no model has seen race before.

Forecast seasonRatings
frozen at
RacesNew
sailors
Coin flipAverage finishEloStatic PLPrevious site modelWeekly PL (site)
Fall 20242024-W364,45995550.0%64.1%66.6%67.0%67.3%67.9%
Spring 20252025-W033,56352250.0%64.9%68.9%68.6%69.8%70.7%
Fall 20252025-W364,21190950.0%64.2%67.3%67.5%68.0%68.6%
Spring 20262026-W033,73271950.0%65.9%69.8%69.1%70.7%71.4%

Championship regattas

Championships are where ratings get the most attention, so this test scores only championship-level fleet regattas: ICSA national finals and semifinals, conference championships and Atlantic Coast Championship rounds, and ISSA national championships, district championships and district qualifiers. For each one, every model is fit on all races through the week before the event and then predicts it. Baseline settings come from that season's forecast tuning.

The site model ordered 72.3% of boat pairs correctly (95% interval 71.5–73.2%) across 166 regattas and 3,114 races; Plackett–Luce, static rating managed 71.2%. Resampling whole regattas, the site model came out ahead of Static PL in 100% of resamples, and the interval for its margin (+0.8 to +1.5 points) stays above zero. With ratings frozen at the start of the season instead, the same model scored 70.8% on these regattas, so results from earlier in the season add real information.

Championship regattas: share of boat pairs ordered correctly, with 95% intervals from resampling whole regattas
50%55%60%65%70%75%No information (coin flip): 50.0% (95% interval 50.0–50.0%)Coin flip50.0%Average finish percentile: 67.0% (95% interval 66.2–67.8%)Average finish67.0%Elo (multi-player, tuned K): 70.9% (95% interval 70.0–71.8%)Elo70.9%Plackett–Luce, static rating: 71.2% (95% interval 70.3–72.2%)Static PL71.2%Plackett–Luce, weekly, before the rating fix (previous site model): 71.9% (95% interval 71.0–72.8%)Previous site model71.9%Plackett–Luce, weekly (site model): 72.3% (95% interval 71.5–73.2%)Weekly PL (site)72.3%
50%55%60%65%70%75%No information (coin flip): 50.0% (95% interval 50.0–50.0%)Coin flip50.0%Average finish percentile: 67.0% (95% interval 66.2–67.8%)Average finish67.0%Elo (multi-player, tuned K): 70.9% (95% interval 70.0–71.8%)Elo70.9%Plackett–Luce, static rating: 71.2% (95% interval 70.3–72.2%)Static PL71.2%Plackett–Luce, weekly, before the rating fix (previous site model): 71.9% (95% interval 71.0–72.8%)Previous site model71.9%Plackett–Luce, weekly (site model): 72.3% (95% interval 71.5–73.2%)Weekly PL (site)72.3%
ModelPairwise
accuracy
95%
interval
Log-lossWinner
picked
ICSAISSASite model
better in
No information (coin flip)50.0%50.0–50.0%0.69328.5%50.0%50.0%100%
Average finish percentile67.0%66.2–67.8%0.605626.8%66.9%67.0%100%
Elo (multi-player, tuned K)70.9%70.0–71.8%0.559230.9%71.5%70.3%100%
Plackett–Luce, static rating71.2%70.3–72.2%0.558132.8%71.8%70.7%100%
Plackett–Luce, weekly, before the rating fix (previous site model)71.9%71.0–72.8%0.546632.7%72.4%71.4%100%
Plackett–Luce, weekly (site model)72.3%71.5–73.2%0.538234.0%72.6%72.0%

Predicted versus actual team totals at every championship

Not every championship is scored yet. Some championship regattas appear on the official scoring sites but their results are not in this site's data, so they are left out: Fall 2024 ICSA 1 of 19.

Missing championship regattas
SeasonLeagueListedScoredMissing
Fall 2024ICSA1918Women's Urn Trophy/NEISA Women’s Fall Champs
Which regattas count as championships
  • ICSA: Conference Championship · 46
  • ICSA: National Championship Finals · 4
  • ICSA: National Championship Semifinals · 8
  • ICSA: Atlantic Coast Championship rounds · 16
  • ISSA: District Champ Qualifier · 50
  • ISSA: District Championship · 40
  • ISSA: National Championship · 2

Fleet race nationals: predicted vs actual

Nationals are the hardest test for the ratings. Each table uses only results from before the week of the regatta: every skipper's rating going in, the standings those ratings predict, and how teams actually finished. Ratings are on the rankings scale, and “new” marks a skipper with no earlier races, who starts at the typical newcomer rating. Predicted points also include each skipper's penalty risk. The chance columns come from simulating the whole regatta, every race and every penalty, thousands of times with those ratings: how often each team won, and how often it finished where it did or better.

Open Fleet Race National Championships Spring 2026 · ICSA · 18 teams

The ratings picked the winner. Predicted totals were off by 27.2 points per team and finishes by 2.7 places, with a rank correlation of 0.80 between predicted and actual standings. Over 14 races per division, the ratings gave Brown University a 31% chance to win, and standings at least this far from the prediction came up in 35% of 2,000 simulated regattas.

Actual
finish
TeamPredicted
finish
Beat
prediction by
Chance of this
finish or better
Win
chance
PointsPredicted
points
Skippers and ratings going in
1Brown University Bears1+031%31%163179.3A Guthrie Braun 492
B Blake Behrens 449
2Stanford University Cardinal3+144%23%174186.7A Thomas Sitzmann 486 (14 races)
B Reade Decker 414 (10 races)
B Vanessa Lahrkamp 505 (4 races)
3Georgetown University Hoyas8+512%2%211248.0A Enzo Menditto 392
B Peter Herlihy 406
3Harvard University Crimson2-163%26%211184.6A Justin Callahan 490
B Mitchell Callahan 426
3Yale University Bulldogs11+86%0%211263.7A Morgan Pinckney 386
B Dorothy Mendelblatt 401
6U. S. Naval Academy Midshipmen7+138%2%223242.3A Nathan Smith 422
B Henry Allgeier 403
7Dartmouth College Big Green9+243%2%225248.2A Ryan Satterberg 406
B Chase Decker 408
7University of Pennsylvania Quakers10+331%1%225261.5A Cole Woodworth 396
B Jackson Mcaliley 394
9Tulane University Green Wave4-584%6%242219.8A Hamilton Barclay 460 (14 races)
B Christian Ebbin 409 (10 races)
B Kelly Holthus 393 (4 races)
10College of Charleston Cougars5-588%5%243223.3A Noah Zittrer 424 (12 races)
A Pierce Olsen 403 (2 races)
B Benjamin Dufour 437 (14 races)
11Roger Williams University Hawks6-585%3%253236.8A Carlos De Castro 458 (14 races)
B Kyle Pfrang 382 (12 races)
B Oliver Stokke 352 (2 races)
12St. Mary's College of Maryland Seahawks13+159%<1%302284.9A Nathan Jensen 363 (12 races)
A Raam Fox 344 (2 races)
B Landon Cormie 389 (14 races)
13Connecticut College Camels18+57%<1%318365.3A Henry Scholz 327 (10 races)
A Rory Murray 270 (4 races)
B William Hurd 289 (14 races)
14Boston College Eagles12-290%<1%321275.8A Tanner Krygsveld 400 (6 races)
A Alex Lech 374 (4 races)
A Peter Busch 381 (2 races)
A Peter Joslin 384 (2 races)
B Caroline Sibilly 382 (6 races)
B Cody Roe 360 (4 races)
B Jack Redmond 395 (4 races)
15Jacksonville University Fins14-179%<1%337305.4A Owen Bannasch 404 (14 races)
B Patrick Igoe 299 (8 races)
B Hank Seum 323 (4 races)
B Cole Schweda 317 (2 races)
16Bowdoin College Polar Bears16+063%<1%343345.0A Michelangelo Vecchio 334 (12 races)
A Ryan Keenan 304 (2 races)
B Kyra Phelan 317 (11 races)
B Lucca Antonietti 288 (3 races)
17Cornell University Big Red15-289%<1%370330.7A Winborne Majette 356 (14 races)
B Gilda Dondona 321 (12 races)
B Marcus Greco 245 (2 races)
18Fordham University Rams17-1>99%<1%380355.1A Jacob Zils 327 (14 races)
B Lucas Thress 312 (8 races)
B Patrick Shachoy 280 (4 races)
B Erickson Rankin 234 (2 races)
Women's Fleet Race National Championhips Spring 2026 · ICSA · 18 teams

The ratings picked the winner. Predicted totals were off by 28.1 points per team and finishes by 2.0 places, with a rank correlation of 0.87 between predicted and actual standings. Over 12 races per division, the ratings gave Stanford University a 76% chance to win, and standings at least this far from the prediction came up in 46% of 2,000 simulated regattas.

Actual
finish
TeamPredicted
finish
Beat
prediction by
Chance of this
finish or better
Win
chance
PointsPredicted
points
Skippers and ratings going in
1Stanford University Cardinal1+076%76%94112.6A Vanessa Lahrkamp 473
B Sophie Fisher 393
2Yale University Bulldogs2+031%7%128165.1A Dorothy Mendelblatt 385
B Carly Kieding 363
3Harvard University Crimson4+127%3%161181.7A Zoey Ziskind 374
B Kate Danielson 338
4Bowdoin College Polar Bears9+511%1%164215.9A Lauren Russler 346
B Kyra Phelan 291
5College of Charleston Cougars6+144%2%171190.2A Bella Shakespeare 352
B Ashley Alfortish 324
5Cornell University Big Red7+241%1%171190.7A Winborne Majette 339 (12 races)
B Sophia Devling 362 (10 races)
B Gilda Dondona 308 (2 races)
7Tulane University Green Wave11+430%1%208220.8A Ava Anderson 365 (12 races)
B Gabriela Vassel 269 (8 races)
B Lola Kohl 244 (4 races)
8Brown University Bears3-587%5%214174.0A Katharine Doble 378 (12 races)
B Katherine Mcnamara 320 (6 races)
B Laura Hamilton 381 (6 races)
9Georgetown University Hoyas5-481%3%226185.9A Emily Doble 341
B Kelly Bates 362
10Roger Williams University Hawks10+059%<1%231220.2A Lucy Meagher 356
B Tavia Smith 270
11Tufts University Jumbos12+157%<1%236234.4A Ella Hubbard 284 (8 races)
A Sophia Hubbard 282 (4 races)
B Maddie Janzen 315 (12 races)
12Dartmouth College Big Green8-495%2%247192.0A Bella Casaretto 366 (11 races)
A Alders Kulynych-Irvin 240 (1 races)
B Olivia Drulard 333 (12 races)
12George Washington University Revolutionaries16+44%<1%247312.8A Arrieta Angueira Salbidegoitia 257
B Hayden Clary 157
14Massachusetts Institute of Technology Engineers14+068%<1%258267.6A Brooke Barry 255 (12 races)
B Karya Basaraner 281 (9 races)
B Emma Wang 234 (3 races)
15Boston College Eagles13-296%<1%276244.9A Caroline Sibilly 394
B Kate Joslin 170
16U. S. Coast Guard Academy Bears15-186%<1%316288.7A Madeline Murphy 267 (12 races)
B Ella Demand 213 (10 races)
B Meara Conley 188 (2 races)
17Jacksonville University Fins18+157%<1%350.1339.1A Kaitlyn Liebel 188 (12 races)
B Fiona Froelich 177 (10 races)
B Kaitlyn Anderson 9 (2 races)
18University of Rhode Island Rams17-1>99%<1%368335.0A Ariana Schwartz 170
B Emaline Ouellette 187
2026 ISSA Mallory National Championship Spring 2026 · ISSA · 20 teams

The ratings picked Point Loma High School; Severn School won. Predicted totals were off by 47.1 points per team and finishes by 2.3 places, with a rank correlation of 0.89 between predicted and actual standings. Over 16 races per division, the ratings gave Severn School a 23% chance to win, and standings at least this far from the prediction came up in 52% of 2,000 simulated regattas.

Actual
finish
TeamPredicted
finish
Beat
prediction by
Chance of this
finish or better
Win
chance
PointsPredicted
points
Skippers and ratings going in
1Severn School Admirals2+123%23%167216.7A Annie Sitzmann 354
B Harrison Szot 364
2Lucy Beckham High School Bengals6+414%6%192262.9A James Pine 382
B Nathan Pine 252
3St. George's School Dragons4+128%7%196254.3A Gil Hackel 379 (16 races)
B Miles Cundey 264 (12 races)
B Amelon Rule 318 (4 races)
4Point Loma High School Pointers1-385%43%200197.1A Wyatt Kelly 369 (13 races)
A Kevin Cason 353 (2 races)
B Anton Schmid 382 (16 races)
5Mater Dei High School Monarchs3-261%10%203241.7A Nickolas Lech 350 (16 races)
B Kingston Keyoung 312 (12 races)
B Colin Kennedy 378 (2 races)
B Gage Christopher 373 (2 races)
6Ransom Everglades School Raiders11+517%<1%229319.3A Ava Mc Aliley 292 (10 races)
A Sander Block 287 (6 races)
B Max Wolfensberger 270 (16 races)
7Barrington High School Eagles7+048%2%304284.6A Duffy Macaulay 355
B Ben Reuter 254
8Christchurch School Seahorses One5-377%5%313260.7A Wylder Smith 352 (16 races)
B Sam De Los Reyes 291 (14 races)
B Elliott Lipp 301 (2 races)
9Gulliver Preparatory School Raiders12+342%1%318323.8A Connor Karr 326 (16 races)
B Arturo Zizold 242 (14 races)
B Danika Torres 121 (2 races)
10Southern Regional High School Rams9-168%1%321299.2A Jude Ryon 317
B Gannon Botwinick 270
11Key School Zags15+412%<1%335412.1A Trey Waters 252 (16 races)
B Casey Burman 174 (14 races)
B Ethan Purdon 104 (2 races)
12Brunswick School Bruins10-275%4%360305.5A Harrison Gandy 299 (14 races)
A Sebastian Sheppard 354 (2 races)
B William Whidden 276 (16 races)
13San Marcos High School Royals8-595%1%365289.9A Dylan Seawards 322 (16 races)
B Sam Wells 303 (12 races)
B Taylor Escola 218 (4 races)
14Arrowhead High School Warhawks13-187%<1%402339.5A John Lieber 248
B Nicholas Berkowitz 281
15Bainbridge High School Spartans14-158%<1%429403.3A Cyrus Yan 187 (10 races)
A Stone Dewey 252 (6 races)
B Nelson Dorsey 219 (16 races)
16Jesuit High School, NOLA Blue Jays20+48%<1%429.7518.5A Jack Meade 199 (14 races)
A Liam Moore 45 (2 races)
B Reed Gibbs new (12 races)
B David Karcher 178 (4 races)
17New Trier HS Trevian17+077%<1%450424.9A Nathan Finkelstein 230 (16 races)
B Aiala Angueira Salbidegoitia 201 (12 races)
B Ralph Lipford 30 (4 races)
18Minnetonka High School Skippers19+162%<1%459461.3A Connor Jewett 216 (12 races)
A Mark Yakovlev new (4 races)
B Reese Kottke 191 (10 races)
B Maggie Mcgary 105 (4 races)
B Maxwell Kelley 89 (2 races)
19Jones College Prep Eagles16-397%<1%460421.3A Nissa Berman 252 (14 races)
A Jack Eskilson 97 (2 races)
B Duke Diep 187 (12 races)
B Quinn Frakt 92 (4 races)
20Olympia High School Bears18-2>99%<1%539457.0A Alan Timms 219 (16 races)
B Simone Reck 150 (10 races)
B Kaden Kim 67 (6 races)
Open Fleet Race National Championships Spring 2025 · ICSA · 18 teams

The ratings picked the winner. Predicted totals were off by 24.1 points per team and finishes by 3.9 places, with a rank correlation of 0.56 between predicted and actual standings. Over 7 races per division, the ratings gave Stanford University a 36% chance to win, and standings at least this far from the prediction came up in 20% of 2,000 simulated regattas.

Actual
finish
TeamPredicted
finish
Beat
prediction by
Chance of this
finish or better
Win
chance
PointsPredicted
points
Skippers and ratings going in
1Stanford University Cardinal1+036%36%5886.3A Thomas Sitzmann 469
B Vanessa Lahrkamp 484
2U. S. Naval Academy Midshipmen8+66%2%74128.9A Nathan Smith 410
B Henry Allgeier 391
3Dartmouth College Big Green12+97%2%91136.5A William Michels 386
B Chase Decker 388
4Yale University Bulldogs3-145%10%98107.3A Jack Egan 430
B Stephan Baker 445
5Harvard University Crimson2-371%21%10797.0A Justin Callahan 498
B Mitchell Callahan 417
6Brown University Bears6+051%6%113114.9A Guthrie Braun 450
B Blake Behrens 401
7Tufts University Jumbos14+722%2%119145.6A Ben Mueller 385
B Kurt Stuebe 359
8George Washington University Revolutionaries18+103%<1%132178.8A Tyler Wood 323
B Jedidiah Bechtel 297
9College of Charleston Cougars4-575%7%135113.3A Noah Zittrer 440
B Benjamin Dufour 413
10Boston College Eagles5-579%7%136114.1A Peter Busch 426 (7 races)
B Jack Redmond 429 (6 races)
B Michael Kirkman 416 (1 races)
11University of Rhode Island Rams9-261%1%140134.2A Kerem Erkmen 455 (6 races)
B Tyler Nash 310 (4 races)
B Christopher Chwalk 285 (3 races)
12Tulane University Green Wave7-589%6%142115.9A Kelly Holthus 407 (6 races)
B Hamilton Barclay 403 (4 races)
B Christian Ebbin 414 (3 races)
13University of Miami Hurricanes13+061%1%148143.7A Atlee Kohl 408
B Aidan Dennis 340
14Bowdoin College Polar Bears17+354%<1%149153.8A Thibault Antonietti 345
B Sam Bonauto 367
15Georgetown University Hoyas11-488%1%151134.9A Piper Holthus 379 (3 races)
A Enzo Menditto 377 (2 races)
A Mateo Di Blasi 429 (2 races)
B Peter Barnard 383 (6 races)
B Diego Escobar 395 (1 races)
16St. Mary's College of Maryland Seahawks10-693%1%168134.7A Owen Hennessey 429 (7 races)
B Landon Cormie 343 (4 races)
B Charlie Anderson 363 (3 races)
17Hobart and William Smith Colleges Statesmen15-293%<1%174150.4A James Kopack 285 (3 races)
A Juan Carlos Lacerda Jones 336 (3 races)
B Jj Klempen 365 (7 races)
18Massachusetts Institute of Technology Engineers16-2>99%<1%206152.6A Sam Bruce 403 (7 races)
B Julius Heitkoetter 307 (5 races)
B William Kulas 330 (2 races)
Women's Fleet Race National Championships Spring 2025 · ICSA · 18 teams

The ratings picked Yale University; Stanford University won. Predicted totals were off by 37.1 points per team and finishes by 2.4 places, with a rank correlation of 0.85 between predicted and actual standings. Over 16 races per division, the ratings gave Stanford University a 30% chance to win, and standings at least this far from the prediction came up in 57% of 2,000 simulated regattas.

Actual
finish
TeamPredicted
finish
Beat
prediction by
Chance of this
finish or better
Win
chance
PointsPredicted
points
Skippers and ratings going in
1Stanford University Cardinal2+130%30%198183.8A Vanessa Lahrkamp 476 (16 races)
B Ellie Harned 350 (8 races)
B Sophie Fisher 370 (8 races)
2Tulane University Green Wave5+313%4%209247.0A Samantha Gardner 392
B Ava Anderson 333
3Harvard University Crimson6+312%1%223271.4A Cordelia Burn 341
B Zoey Ziskind 345
4Yale University Bulldogs1-398%58%250165.2A Emma Cowles 430 (8 races)
A Mia Nicolosi 463 (8 races)
B Carmen Cowles 422 (16 races)
5Cornell University Big Red3-264%4%255240.6A Bridget Green 424 (12 races)
A Winborne Majette 353 (4 races)
B Sophia Devling 330 (16 races)
6Boston College Eagles10+414%<1%277323.8A Caroline Sibilly 363
B Sara Schumann 244
7Georgetown University Hoyas4-385%4%284241.0A Piper Holthus 379 (16 races)
B Emily Doble 357 (8 races)
B Kelly Bates 352 (8 races)
8Bowdoin College Polar Bears12+427%<1%287332.2A Kyra Phelan 305
B Lauren Russler 289
9Brown University Bears7-261%<1%294295.7A Katharine Doble 327 (16 races)
B Katherine Mcnamara 324 (10 races)
B Laura Hamilton 319 (6 races)
10Dartmouth College Big Green9-160%<1%297310.3A Sarah Young 348 (14 races)
A Bella Casaretto 341 (2 races)
B Olivia Drulard 281 (16 races)
11College of Charleston Cougars11+056%<1%307324.4A Emma Tallman 331
B Emily Alfortish 278
12George Washington University Revolutionaries17+512%<1%314401.5A Avery Canavan 239
B Arrieta Angueira Salbidegoitia 241
13Massachusetts Institute of Technology Engineers8-587%<1%320303.9A Brooke Schmelz 323
B Lucy Brock 313
13Northeastern University Huskies15+250%<1%320357.2A Eva Ermlich 276
B Lucia Loosbrock 279
15Roger Williams University Hawks14-181%<1%371345.6A Lucy Meagher 334 (16 races)
B Tavia Smith 256 (10 races)
B Katherine Mcgagh 211 (6 races)
16University of Pennsylvania Quakers13-394%<1%388334.2A Sofia Segalla 333
B Adra Ivancich 259
17University of South Florida Bulls16-184%<1%426384.7A Kay Brunsvold 302 (15 races)
A Kailey Warrior 211 (1 races)
B Kalea Woodard 218 (14 races)
B Heidi Hicks 179 (2 races)
18Tufts University Jumbos18+0>99%<1%453414.0A Maisie Macgillivray 199 (6 races)
A Meredith Broadus 207 (6 races)
A Kiana Beachy 196 (4 races)
B Sophia Hubbard 251 (16 races)
ISSA Fleet Nationals (Mallory Trophy) Spring 2025 · ISSA · 20 teams

The ratings picked the winner. Predicted totals were off by 36.9 points per team and finishes by 1.9 places, with a rank correlation of 0.91 between predicted and actual standings. Over 20 races per division, the ratings gave Point Loma High School a 43% chance to win, and standings at least this far from the prediction came up in 70% of 2,000 simulated regattas.

Actual
finish
TeamPredicted
finish
Beat
prediction by
Chance of this
finish or better
Win
chance
PointsPredicted
points
Skippers and ratings going in
1Point Loma High School Pointers1+043%43%266.6241.4A Ian Nyenhuis 412
B Anton Schmid 417
2Antilles School Hurricanes3+127%15%270299.8A Tanner Krygsveld 427
B Cobia Fagan 280
3Ransom Everglades School Raiders6+322%3%294326.0A Griggs Diemar 389 (20 races)
B Sebastian Van De Kreeke 288 (16 races)
B Ava Mc Aliley 234 (4 races)
4Severn School Admirals4+050%7%301301.3A Harrison Szot 339 (12 races)
A Alex Baker 330 (8 races)
B Annie Sitzmann 365 (20 races)
5Christchurch School Seahorses5+060%7%307.8304.7A Bo Angus 367 (16 races)
A Madeline Janzen 254 (4 races)
B Wylder Smith 352 (20 races)
6Lucy Beckham High School Bengals9+323%1%326380.7A James Pine 359
B Nathan Pine 241
7Mater Dei High School Monarchs2-596%22%327264.1A Tate Christopher 403 (20 races)
B Brady Kennedy 343 (10 races)
B Noah Stapleton 349 (10 races)
7St. George's School Dragons11+428%<1%327392.9A Gil Hackel 310 (20 races)
B Amelon Rule 287 (18 races)
B Kai Watters 160 (2 races)
9Tabor Academy Seawolves10+148%1%345392.4A Peter Herlihy 339 (20 races)
B Jack Spillane 257 (16 races)
B Perrin Mueller 204 (2 races)
B Sander Skaane 197 (2 races)
10The Hotchkiss School Bearcats7-371%1%351367.8A Pierce Olsen 337 (20 races)
B Thomas O'Grady 265 (11 races)
B Fynn Olsen 298 (9 races)
11Southern Regional High School Rams12+154%<1%407417.5A Turner Ryon 271 (16 races)
A Gannon Botwinick 220 (4 races)
B Jude Ryon 293 (20 races)
12Corona del Mar High School Sea Kings13+161%<1%443427.8A Michael Sentovich 275 (20 races)
B Maddie Nichols 289 (12 races)
B Siena Nichols 269 (6 races)
B Jonah Moore 123 (2 races)
13Christian Brothers Academy Colts8-595%<1%444374.0A Christopher Small 319
B Cole Buczkowski 287
14Jones College Prep Eagles16+224%<1%445526.0A Nissa Berman 216
B Grace Renz 203
15Wayzata High School Navy18+37%<1%544587.7A Dominik Moncur 227
B Stonewall Anderson 69
16Arrowhead High School Warhawks14-291%<1%547469.6A John Lieber 246
B Nicholas Berkowitz 246
17Lake Forest High School Scouts15-285%<1%559515.4A Mason Keane 230 (13 races)
A Grady Strothman 261 (4 races)
A Owen Kohut 331 (3 races)
B Keegan Chatburn 218 (14 races)
B Maddie Rode 98 (4 races)
B Jackson Schwartz 61 (2 races)
18Olympia High School Bears19+152%<1%603600.6A Alan Timms 176
B Liam Taylor 141
19Clear Lake High School Falcons Green17-283%<1%621578.2A Sydney Small 234
B Casey Small 111
20Roosevelt High School Rough Riders20+0>99%<1%643629.6A Roan Olson 142
B Ethan Lee 128

Predicted versus actual standings at every championship

Races within a regatta are not independent

The model predicts each race from ratings alone, as if every race were a fresh draw. Real regattas are not like that: a sailor who beats their rating in one race tends to beat it again. To measure it, each championship skipper's result in every race was scored against their rating going in (places better or worse than expected, as a share of the fleet), then compared race by race, with up to 4,440 sailors behind each pair of races. If races were independent every cell below would be about zero.

Correlation between a sailor's result against their rating in race i (rows) and race j (columns), championship divisions with ratings frozen the week before. Darker means more alike.
1234567891011121Race 1 and race 2: correlation +0.30 (4,440 sailors)0.30Race 1 and race 3: correlation +0.22 (4,213 sailors)0.22Race 1 and race 4: correlation +0.20 (4,104 sailors)0.20Race 1 and race 5: correlation +0.20 (3,853 sailors)0.20Race 1 and race 6: correlation +0.17 (3,775 sailors)0.17Race 1 and race 7: correlation +0.17 (3,376 sailors)0.17Race 1 and race 8: correlation +0.15 (3,034 sailors)0.15Race 1 and race 9: correlation +0.13 (2,502 sailors)0.13Race 1 and race 10: correlation +0.14 (2,195 sailors)0.14Race 1 and race 11: correlation +0.14 (1,514 sailors)0.14Race 1 and race 12: correlation +0.09 (1,304 sailors)0.092Race 2 and race 1: correlation +0.30 (4,440 sailors)0.30Race 2 and race 3: correlation +0.21 (4,240 sailors)0.21Race 2 and race 4: correlation +0.21 (4,129 sailors)0.21Race 2 and race 5: correlation +0.20 (3,874 sailors)0.20Race 2 and race 6: correlation +0.17 (3,800 sailors)0.17Race 2 and race 7: correlation +0.19 (3,396 sailors)0.19Race 2 and race 8: correlation +0.16 (3,054 sailors)0.16Race 2 and race 9: correlation +0.13 (2,516 sailors)0.13Race 2 and race 10: correlation +0.13 (2,210 sailors)0.13Race 2 and race 11: correlation +0.13 (1,526 sailors)0.13Race 2 and race 12: correlation +0.09 (1,317 sailors)0.093Race 3 and race 1: correlation +0.22 (4,213 sailors)0.22Race 3 and race 2: correlation +0.21 (4,240 sailors)0.21Race 3 and race 4: correlation +0.27 (4,284 sailors)0.27Race 3 and race 5: correlation +0.18 (3,830 sailors)0.18Race 3 and race 6: correlation +0.19 (3,757 sailors)0.19Race 3 and race 7: correlation +0.17 (3,400 sailors)0.17Race 3 and race 8: correlation +0.14 (3,064 sailors)0.14Race 3 and race 9: correlation +0.15 (2,483 sailors)0.15Race 3 and race 10: correlation +0.14 (2,174 sailors)0.14Race 3 and race 11: correlation +0.12 (1,523 sailors)0.12Race 3 and race 12: correlation +0.09 (1,305 sailors)0.094Race 4 and race 1: correlation +0.20 (4,104 sailors)0.20Race 4 and race 2: correlation +0.21 (4,129 sailors)0.21Race 4 and race 3: correlation +0.27 (4,284 sailors)0.27Race 4 and race 5: correlation +0.20 (3,867 sailors)0.20Race 4 and race 6: correlation +0.19 (3,782 sailors)0.19Race 4 and race 7: correlation +0.18 (3,416 sailors)0.18Race 4 and race 8: correlation +0.18 (3,067 sailors)0.18Race 4 and race 9: correlation +0.12 (2,488 sailors)0.12Race 4 and race 10: correlation +0.10 (2,171 sailors)0.10Race 4 and race 11: correlation +0.13 (1,519 sailors)0.13Race 4 and race 12: correlation +0.10 (1,303 sailors)0.105Race 5 and race 1: correlation +0.20 (3,853 sailors)0.20Race 5 and race 2: correlation +0.20 (3,874 sailors)0.20Race 5 and race 3: correlation +0.18 (3,830 sailors)0.18Race 5 and race 4: correlation +0.20 (3,867 sailors)0.20Race 5 and race 6: correlation +0.23 (4,085 sailors)0.23Race 5 and race 7: correlation +0.18 (3,462 sailors)0.18Race 5 and race 8: correlation +0.17 (3,100 sailors)0.17Race 5 and race 9: correlation +0.17 (2,504 sailors)0.17Race 5 and race 10: correlation +0.14 (2,192 sailors)0.14Race 5 and race 11: correlation +0.13 (1,502 sailors)0.13Race 5 and race 12: correlation +0.07 (1,289 sailors)0.076Race 6 and race 1: correlation +0.17 (3,775 sailors)0.17Race 6 and race 2: correlation +0.17 (3,800 sailors)0.17Race 6 and race 3: correlation +0.19 (3,757 sailors)0.19Race 6 and race 4: correlation +0.19 (3,782 sailors)0.19Race 6 and race 5: correlation +0.23 (4,085 sailors)0.23Race 6 and race 7: correlation +0.19 (3,479 sailors)0.19Race 6 and race 8: correlation +0.17 (3,118 sailors)0.17Race 6 and race 9: correlation +0.12 (2,507 sailors)0.12Race 6 and race 10: correlation +0.16 (2,198 sailors)0.16Race 6 and race 11: correlation +0.09 (1,504 sailors)0.09Race 6 and race 12: correlation +0.04 (1,288 sailors)0.047Race 7 and race 1: correlation +0.17 (3,376 sailors)0.17Race 7 and race 2: correlation +0.19 (3,396 sailors)0.19Race 7 and race 3: correlation +0.17 (3,400 sailors)0.17Race 7 and race 4: correlation +0.18 (3,416 sailors)0.18Race 7 and race 5: correlation +0.18 (3,462 sailors)0.18Race 7 and race 6: correlation +0.19 (3,479 sailors)0.19Race 7 and race 8: correlation +0.29 (3,406 sailors)0.29Race 7 and race 9: correlation +0.18 (2,594 sailors)0.18Race 7 and race 10: correlation +0.18 (2,265 sailors)0.18Race 7 and race 11: correlation +0.13 (1,549 sailors)0.13Race 7 and race 12: correlation +0.10 (1,326 sailors)0.108Race 8 and race 1: correlation +0.15 (3,034 sailors)0.15Race 8 and race 2: correlation +0.16 (3,054 sailors)0.16Race 8 and race 3: correlation +0.14 (3,064 sailors)0.14Race 8 and race 4: correlation +0.18 (3,067 sailors)0.18Race 8 and race 5: correlation +0.17 (3,100 sailors)0.17Race 8 and race 6: correlation +0.17 (3,118 sailors)0.17Race 8 and race 7: correlation +0.29 (3,406 sailors)0.29Race 8 and race 9: correlation +0.16 (2,600 sailors)0.16Race 8 and race 10: correlation +0.16 (2,268 sailors)0.16Race 8 and race 11: correlation +0.14 (1,544 sailors)0.14Race 8 and race 12: correlation +0.12 (1,321 sailors)0.129Race 9 and race 1: correlation +0.13 (2,502 sailors)0.13Race 9 and race 2: correlation +0.13 (2,516 sailors)0.13Race 9 and race 3: correlation +0.15 (2,483 sailors)0.15Race 9 and race 4: correlation +0.12 (2,488 sailors)0.12Race 9 and race 5: correlation +0.17 (2,504 sailors)0.17Race 9 and race 6: correlation +0.12 (2,507 sailors)0.12Race 9 and race 7: correlation +0.18 (2,594 sailors)0.18Race 9 and race 8: correlation +0.16 (2,600 sailors)0.16Race 9 and race 10: correlation +0.27 (2,496 sailors)0.27Race 9 and race 11: correlation +0.17 (1,623 sailors)0.17Race 9 and race 12: correlation +0.16 (1,407 sailors)0.1610Race 10 and race 1: correlation +0.14 (2,195 sailors)0.14Race 10 and race 2: correlation +0.13 (2,210 sailors)0.13Race 10 and race 3: correlation +0.14 (2,174 sailors)0.14Race 10 and race 4: correlation +0.10 (2,171 sailors)0.10Race 10 and race 5: correlation +0.14 (2,192 sailors)0.14Race 10 and race 6: correlation +0.16 (2,198 sailors)0.16Race 10 and race 7: correlation +0.18 (2,265 sailors)0.18Race 10 and race 8: correlation +0.16 (2,268 sailors)0.16Race 10 and race 9: correlation +0.27 (2,496 sailors)0.27Race 10 and race 11: correlation +0.19 (1,635 sailors)0.19Race 10 and race 12: correlation +0.19 (1,416 sailors)0.1911Race 11 and race 1: correlation +0.14 (1,514 sailors)0.14Race 11 and race 2: correlation +0.13 (1,526 sailors)0.13Race 11 and race 3: correlation +0.12 (1,523 sailors)0.12Race 11 and race 4: correlation +0.13 (1,519 sailors)0.13Race 11 and race 5: correlation +0.13 (1,502 sailors)0.13Race 11 and race 6: correlation +0.09 (1,504 sailors)0.09Race 11 and race 7: correlation +0.13 (1,549 sailors)0.13Race 11 and race 8: correlation +0.14 (1,544 sailors)0.14Race 11 and race 9: correlation +0.17 (1,623 sailors)0.17Race 11 and race 10: correlation +0.19 (1,635 sailors)0.19Race 11 and race 12: correlation +0.28 (1,506 sailors)0.2812Race 12 and race 1: correlation +0.09 (1,304 sailors)0.09Race 12 and race 2: correlation +0.09 (1,317 sailors)0.09Race 12 and race 3: correlation +0.09 (1,305 sailors)0.09Race 12 and race 4: correlation +0.10 (1,303 sailors)0.10Race 12 and race 5: correlation +0.07 (1,289 sailors)0.07Race 12 and race 6: correlation +0.04 (1,288 sailors)0.04Race 12 and race 7: correlation +0.10 (1,326 sailors)0.10Race 12 and race 8: correlation +0.12 (1,321 sailors)0.12Race 12 and race 9: correlation +0.16 (1,407 sailors)0.16Race 12 and race 10: correlation +0.19 (1,416 sailors)0.19Race 12 and race 11: correlation +0.28 (1,506 sailors)0.280.00.10.20.3correlation
1234567891011121Race 1 and race 2: correlation +0.30 (4,440 sailors)Race 1 and race 3: correlation +0.22 (4,213 sailors)Race 1 and race 4: correlation +0.20 (4,104 sailors)Race 1 and race 5: correlation +0.20 (3,853 sailors)Race 1 and race 6: correlation +0.17 (3,775 sailors)Race 1 and race 7: correlation +0.17 (3,376 sailors)Race 1 and race 8: correlation +0.15 (3,034 sailors)Race 1 and race 9: correlation +0.13 (2,502 sailors)Race 1 and race 10: correlation +0.14 (2,195 sailors)Race 1 and race 11: correlation +0.14 (1,514 sailors)Race 1 and race 12: correlation +0.09 (1,304 sailors)2Race 2 and race 1: correlation +0.30 (4,440 sailors)Race 2 and race 3: correlation +0.21 (4,240 sailors)Race 2 and race 4: correlation +0.21 (4,129 sailors)Race 2 and race 5: correlation +0.20 (3,874 sailors)Race 2 and race 6: correlation +0.17 (3,800 sailors)Race 2 and race 7: correlation +0.19 (3,396 sailors)Race 2 and race 8: correlation +0.16 (3,054 sailors)Race 2 and race 9: correlation +0.13 (2,516 sailors)Race 2 and race 10: correlation +0.13 (2,210 sailors)Race 2 and race 11: correlation +0.13 (1,526 sailors)Race 2 and race 12: correlation +0.09 (1,317 sailors)3Race 3 and race 1: correlation +0.22 (4,213 sailors)Race 3 and race 2: correlation +0.21 (4,240 sailors)Race 3 and race 4: correlation +0.27 (4,284 sailors)Race 3 and race 5: correlation +0.18 (3,830 sailors)Race 3 and race 6: correlation +0.19 (3,757 sailors)Race 3 and race 7: correlation +0.17 (3,400 sailors)Race 3 and race 8: correlation +0.14 (3,064 sailors)Race 3 and race 9: correlation +0.15 (2,483 sailors)Race 3 and race 10: correlation +0.14 (2,174 sailors)Race 3 and race 11: correlation +0.12 (1,523 sailors)Race 3 and race 12: correlation +0.09 (1,305 sailors)4Race 4 and race 1: correlation +0.20 (4,104 sailors)Race 4 and race 2: correlation +0.21 (4,129 sailors)Race 4 and race 3: correlation +0.27 (4,284 sailors)Race 4 and race 5: correlation +0.20 (3,867 sailors)Race 4 and race 6: correlation +0.19 (3,782 sailors)Race 4 and race 7: correlation +0.18 (3,416 sailors)Race 4 and race 8: correlation +0.18 (3,067 sailors)Race 4 and race 9: correlation +0.12 (2,488 sailors)Race 4 and race 10: correlation +0.10 (2,171 sailors)Race 4 and race 11: correlation +0.13 (1,519 sailors)Race 4 and race 12: correlation +0.10 (1,303 sailors)5Race 5 and race 1: correlation +0.20 (3,853 sailors)Race 5 and race 2: correlation +0.20 (3,874 sailors)Race 5 and race 3: correlation +0.18 (3,830 sailors)Race 5 and race 4: correlation +0.20 (3,867 sailors)Race 5 and race 6: correlation +0.23 (4,085 sailors)Race 5 and race 7: correlation +0.18 (3,462 sailors)Race 5 and race 8: correlation +0.17 (3,100 sailors)Race 5 and race 9: correlation +0.17 (2,504 sailors)Race 5 and race 10: correlation +0.14 (2,192 sailors)Race 5 and race 11: correlation +0.13 (1,502 sailors)Race 5 and race 12: correlation +0.07 (1,289 sailors)6Race 6 and race 1: correlation +0.17 (3,775 sailors)Race 6 and race 2: correlation +0.17 (3,800 sailors)Race 6 and race 3: correlation +0.19 (3,757 sailors)Race 6 and race 4: correlation +0.19 (3,782 sailors)Race 6 and race 5: correlation +0.23 (4,085 sailors)Race 6 and race 7: correlation +0.19 (3,479 sailors)Race 6 and race 8: correlation +0.17 (3,118 sailors)Race 6 and race 9: correlation +0.12 (2,507 sailors)Race 6 and race 10: correlation +0.16 (2,198 sailors)Race 6 and race 11: correlation +0.09 (1,504 sailors)Race 6 and race 12: correlation +0.04 (1,288 sailors)7Race 7 and race 1: correlation +0.17 (3,376 sailors)Race 7 and race 2: correlation +0.19 (3,396 sailors)Race 7 and race 3: correlation +0.17 (3,400 sailors)Race 7 and race 4: correlation +0.18 (3,416 sailors)Race 7 and race 5: correlation +0.18 (3,462 sailors)Race 7 and race 6: correlation +0.19 (3,479 sailors)Race 7 and race 8: correlation +0.29 (3,406 sailors)Race 7 and race 9: correlation +0.18 (2,594 sailors)Race 7 and race 10: correlation +0.18 (2,265 sailors)Race 7 and race 11: correlation +0.13 (1,549 sailors)Race 7 and race 12: correlation +0.10 (1,326 sailors)8Race 8 and race 1: correlation +0.15 (3,034 sailors)Race 8 and race 2: correlation +0.16 (3,054 sailors)Race 8 and race 3: correlation +0.14 (3,064 sailors)Race 8 and race 4: correlation +0.18 (3,067 sailors)Race 8 and race 5: correlation +0.17 (3,100 sailors)Race 8 and race 6: correlation +0.17 (3,118 sailors)Race 8 and race 7: correlation +0.29 (3,406 sailors)Race 8 and race 9: correlation +0.16 (2,600 sailors)Race 8 and race 10: correlation +0.16 (2,268 sailors)Race 8 and race 11: correlation +0.14 (1,544 sailors)Race 8 and race 12: correlation +0.12 (1,321 sailors)9Race 9 and race 1: correlation +0.13 (2,502 sailors)Race 9 and race 2: correlation +0.13 (2,516 sailors)Race 9 and race 3: correlation +0.15 (2,483 sailors)Race 9 and race 4: correlation +0.12 (2,488 sailors)Race 9 and race 5: correlation +0.17 (2,504 sailors)Race 9 and race 6: correlation +0.12 (2,507 sailors)Race 9 and race 7: correlation +0.18 (2,594 sailors)Race 9 and race 8: correlation +0.16 (2,600 sailors)Race 9 and race 10: correlation +0.27 (2,496 sailors)Race 9 and race 11: correlation +0.17 (1,623 sailors)Race 9 and race 12: correlation +0.16 (1,407 sailors)10Race 10 and race 1: correlation +0.14 (2,195 sailors)Race 10 and race 2: correlation +0.13 (2,210 sailors)Race 10 and race 3: correlation +0.14 (2,174 sailors)Race 10 and race 4: correlation +0.10 (2,171 sailors)Race 10 and race 5: correlation +0.14 (2,192 sailors)Race 10 and race 6: correlation +0.16 (2,198 sailors)Race 10 and race 7: correlation +0.18 (2,265 sailors)Race 10 and race 8: correlation +0.16 (2,268 sailors)Race 10 and race 9: correlation +0.27 (2,496 sailors)Race 10 and race 11: correlation +0.19 (1,635 sailors)Race 10 and race 12: correlation +0.19 (1,416 sailors)11Race 11 and race 1: correlation +0.14 (1,514 sailors)Race 11 and race 2: correlation +0.13 (1,526 sailors)Race 11 and race 3: correlation +0.12 (1,523 sailors)Race 11 and race 4: correlation +0.13 (1,519 sailors)Race 11 and race 5: correlation +0.13 (1,502 sailors)Race 11 and race 6: correlation +0.09 (1,504 sailors)Race 11 and race 7: correlation +0.13 (1,549 sailors)Race 11 and race 8: correlation +0.14 (1,544 sailors)Race 11 and race 9: correlation +0.17 (1,623 sailors)Race 11 and race 10: correlation +0.19 (1,635 sailors)Race 11 and race 12: correlation +0.28 (1,506 sailors)12Race 12 and race 1: correlation +0.09 (1,304 sailors)Race 12 and race 2: correlation +0.09 (1,317 sailors)Race 12 and race 3: correlation +0.09 (1,305 sailors)Race 12 and race 4: correlation +0.10 (1,303 sailors)Race 12 and race 5: correlation +0.07 (1,289 sailors)Race 12 and race 6: correlation +0.04 (1,288 sailors)Race 12 and race 7: correlation +0.10 (1,326 sailors)Race 12 and race 8: correlation +0.12 (1,321 sailors)Race 12 and race 9: correlation +0.16 (1,407 sailors)Race 12 and race 10: correlation +0.19 (1,416 sailors)Race 12 and race 11: correlation +0.28 (1,506 sailors)0.00.10.20.3correlation

Every pair of races is positively correlated, 0.16 on average. Back-to-back races are the most alike (0.24) and the link fades with distance, to 0.09 for races 11 apart, so part of it is form or conditions that change through the regatta. Races also come in pairs: back-to-back races within the same pair (1–2, 3–4, …) average 0.27, while back-to-back races across a pair (2–3, 4–5, …) average 0.19. Rotations show why. Back-to-back races sailed in the same boat correlate at 0.27, back-to-back races in different boats at 0.18. The boat matters even when races are far apart: 2 races apart, the same boat gives 0.35 and a different boat 0.18.

Average correlation by how many races apart, with what two simple models would produce on the same fleets: independent races, and one form offset per sailor that lasts the whole regatta (a flat 0.17).
0.00.10.20.312345678910111 race apart: correlation +0.238 (36,038 pairs)2 races apart: correlation +0.187 (30,435 pairs)3 races apart: correlation +0.179 (25,974 pairs)4 races apart: correlation +0.168 (21,692 pairs)5 races apart: correlation +0.145 (17,745 pairs)6 races apart: correlation +0.137 (13,874 pairs)7 races apart: correlation +0.132 (10,532 pairs)8 races apart: correlation +0.122 (7,538 pairs)9 races apart: correlation +0.125 (5,026 pairs)10 races apart: correlation +0.115 (2,831 pairs)11 races apart: correlation +0.094 (1,304 pairs)Regatta offsetReal resultsIndependentRaces apartCorrelation
0.00.10.20.312345678910111 race apart: correlation +0.238 (36,038 pairs)2 races apart: correlation +0.187 (30,435 pairs)3 races apart: correlation +0.179 (25,974 pairs)4 races apart: correlation +0.168 (21,692 pairs)5 races apart: correlation +0.145 (17,745 pairs)6 races apart: correlation +0.137 (13,874 pairs)7 races apart: correlation +0.132 (10,532 pairs)8 races apart: correlation +0.122 (7,538 pairs)9 races apart: correlation +0.125 (5,026 pairs)10 races apart: correlation +0.115 (2,831 pairs)11 races apart: correlation +0.094 (1,304 pairs)Regatta offsetReal resultsIndependentRaces apartCorrelation

So yes, winning race 1 means something. Across 265 championship divisions, the race-1 winner went on to average 4.4 in later races. Their rating alone predicted 5.2; updating on race 1 predicts 4.7.

Using it. If each sailor's strength is nudged by how they have sailed so far in the regatta, the order of later races is easier to predict. Tuned on 2024–25 championships and tested on 2025–26, pairs ordered correctly rose from 72.9% to 74.5% and log-loss fell from 0.534 to 0.514. That is a bigger gain than the site model's whole edge over Elo.

In the simulations. The championship simulations and the regatta analysis pages now build these correlations into every simulated regatta instead of treating each race as a fresh draw. Each sailor gets a good or bad regatta, form that drifts from race to race, and the speed of whichever boat the rotation puts them in, shared with every team that sails that boat. The three sizes were fitted to the correlations above. How big the swings should be depends on how well a sailor's rating is known, because they also cover the rating being wrong. For skippers with more than 200 races before the event they are 0.6 times the fitted size; for 61–200 races 0.7; for 1–60 races 1.3; for newcomers 2.0. Those sizes were chosen on the 2024–25 championships and checked on 2025–26 (the newcomers still finish worse than their starting rating suggests, which bigger swings cannot fix). Before both changes, team totals needed much smaller swings than individual sailors did: championship winners are mostly experienced skippers with well-known ratings, and extra swings were also flattening favourites whose ratings were already too bunched. With both, team totals chose 100% of the fitted size. See how likely was each result.

Are the probabilities honest?

When the model says a sailor has a 70% chance of finishing ahead of another, that should happen about 70% of the time. Points on the diagonal mean the stated probabilities can be taken at face value. Up to about 85% confidence the points sit within 4.2 percentage points of the diagonal. Above that the model is slightly overconfident: when it says 97%, the favourite finishes ahead 90% of the time.

Calibration of the site model, all forecast seasons pooled. Each blue point groups boat pairs by how confident the model was in the favourite; the gray line is perfect calibration.
50%50%60%60%70%70%80%80%90%90%100%100%Model said 53% · favourite finished ahead 52% of the time · 144,554 pairsModel said 57% · favourite finished ahead 56% of the time · 145,299 pairsModel said 62% · favourite finished ahead 61% of the time · 141,952 pairsModel said 67% · favourite finished ahead 65% of the time · 136,003 pairsModel said 72% · favourite finished ahead 70% of the time · 134,944 pairsModel said 77% · favourite finished ahead 74% of the time · 131,363 pairsModel said 83% · favourite finished ahead 78% of the time · 130,268 pairsModel said 87% · favourite finished ahead 83% of the time · 121,292 pairsModel said 92% · favourite finished ahead 88% of the time · 120,611 pairsModel said 97% · favourite finished ahead 90% of the time · 92,542 pairsModel's probability the favourite finishes aheadHow often the favourite actually did
50%50%60%60%70%70%80%80%90%90%100%100%Model said 53% · favourite finished ahead 52% of the time · 144,554 pairsModel said 57% · favourite finished ahead 56% of the time · 145,299 pairsModel said 62% · favourite finished ahead 61% of the time · 141,952 pairsModel said 67% · favourite finished ahead 65% of the time · 136,003 pairsModel said 72% · favourite finished ahead 70% of the time · 134,944 pairsModel said 77% · favourite finished ahead 74% of the time · 131,363 pairsModel said 83% · favourite finished ahead 78% of the time · 130,268 pairsModel said 87% · favourite finished ahead 83% of the time · 121,292 pairsModel said 92% · favourite finished ahead 88% of the time · 120,611 pairsModel said 97% · favourite finished ahead 90% of the time · 92,542 pairsModel's probability the favourite finishes aheadHow often the favourite actually did
Calibration table
Confidence binMean predictedObservedPairs
50–55%52.5%52.3%144,554
55–60%57.5%56.1%145,299
60–65%62.5%60.5%141,952
65–70%67.5%65.0%136,003
70–75%72.5%69.8%134,944
75–80%77.5%73.8%131,363
80–85%82.5%78.3%130,268
85–90%87.5%82.9%121,292
90–95%92.5%87.6%120,611
95–100%97.0%90.1%92,542

Penalties

An OCS or a DNF says little about boat speed, so boats that did not finish are left out of each race's finishing order. They never count as losing to every boat that finished, and they are left out of the accuracy numbers above. Penalties are predicted separately: each skipper gets a per-race chance of a start penalty, a DNF and a DNS, pulled toward the league rate by an amount tuned on the previous season, so a few penalties in a handful of races do not brand a sailor. The tenth of race entries it rated most penalty-prone had a penalty 2.9% of the time, against 2.0% for everyone else.

OutcomeShare of
race entries
Log-loss vs
league rate
Championships:
share
Championships:
vs league rate
Start penalty (OCS)0.26%+0.1%0.32%+0.3%
Did not finish (DNF, RAF)0.66%+1.0%0.41%+3.3%
Did not start (DNS)1.15%+1.6%0.70%+8.0%
Any of these2.07%+1.6%1.43%+5.2%

“Log-loss vs league rate” is how much better the penalty scores predict than giving every skipper the league's average rate, season-ahead and at championships. Penalties are rare and only loosely a habit, so these gains are small; did not start is the most predictable.

Sanity check: the trainer's own test split

The trainer holds out every 20th regatta (334 regattas, 3,588 races) and prints its accuracy on them. Re-scoring that split with this evaluator should reproduce the trainer's numbers, which confirms the metric code. These figures are optimistic for the two Plackett–Luce models: the weekly model smooths ratings across time, so a held-out race's rating is informed by races that came after it. Elo and average finish only use earlier weeks here.

ModelICSA
accuracy
ICSA
log-loss
ISSA
accuracy
ISSA
log-loss
No information (coin flip)50.0%0.693250.0%0.6932
Average finish percentile63.3%0.633367.4%0.5981
Elo (multi-player, tuned K)68.1%0.589570.9%0.5644
Plackett–Luce, static rating71.1%0.548673.5%0.5278
Plackett–Luce, weekly, before the rating fix (previous site model)70.9%0.558573.7%0.5317
Plackett–Luce, weekly (site model)71.7%0.542574.6%0.5122
Trainer's own printout (weekly PL)71.68%0.542574.61%0.5122

Caveats

  • The weekly model's smoothing settings came from an earlier search scored on randomly held-out regattas that include these seasons, so its settings carry a little information from the forecast period. Baselines were tuned strictly forward.
  • Pairs are pooled, so large fleets weigh more than small ones.
  • Boats that did not finish are ordered last; the order among several non-finishers in the same race is arbitrary and counts against every model equally.
  • Only skippers are rated. Singlehanded events and regattas without a date are excluded, matching the model's training data.
  • High school and college profiles of the same sailor are linked before training, so a freshman with a high school record counts as a returning sailor.

Tuned baseline settings

Forecast seasonTuned onElo KAvg-finish
shrinkage
Static PL
L2 λ
Fall 2024Spring 20246433
Spring 2025Fall 202464206
Fall 2025Spring 2025128103
Spring 2026Fall 202564206

Reproduce

python3 analysis/plackett_luce/evaluate_models.py

Generated 2026-09-15 from 102,091 races and 24,501 sailors (2008-W38 to 2026-W37). Full run 91 minutes.