J70 Tuesday Invite - 1

# SchoolTeam A TOT
1 Tufts University Tufts University Jumbos 2 10 10
2 Brown University Brown University Bears 14 14
3 U. S. Coast Guard Academy U. S. Coast Guard Academy Bears 1 15 15
4 Tufts University Tufts University Jumbos 1 19 19
5 U. S. Coast Guard Academy U. S. Coast Guard Academy Bears 2 25 25
6 U. S. Coast Guard Academy U. S. Coast Guard Academy Bears 3 28 28
7 University of Rhode Island University of Rhode Island Rams 29 29
SchoolTeam R1 R2 R3 R4 R5 TOT
Tufts University Tufts University Jumbos 2 2 1 4 1 2 10
Brown University Brown University Bears 6 2 3 2 1 14
U. S. Coast Guard Academy U. S. Coast Guard Academy Bears 1 3 4 2 3 3 15
Tufts University Tufts University Jumbos 1 1 7 1 5 5 19
U. S. Coast Guard Academy U. S. Coast Guard Academy Bears 2 5 3 6 4 7 25
U. S. Coast Guard Academy U. S. Coast Guard Academy Bears 3 7 5 5 7 4 28
University of Rhode Island University of Rhode Island Rams 4 6 7 6 6 29

Performance rating asks, for each skipper: holding every other boat fixed, which rating makes my actual race-by-race finishes least surprising? Boats are valued with the keelboat rating rather than the fleet rating: 0.41 × the skipper's fleet rating from the week before the event (unrated skippers start at 0.47); 0.28 × the mean fleet rating of the rated crew aboard; the skipper's own keelboat offset; the school's program effect. Non-finishes (OCS, DNF and similar) are left out of the fitting, as in the rating model.

Percentile places a rating among the 207 ICSA sailors with a keelboat rating who raced the discipline in the last three seasons. Surprise is how many bits more surprising the finishes were at the pre-event rating than at the performance rating. P(this good or better) simulates the event 3,000 times at the pre-event ratings, with the same regatta-form model as the fleet analysis pages, and reports how often the skipper would score this many points or fewer in the races they sailed.

The keelboat offsets are the current ones (the discipline files keep no weekly history), so a skipper's own offset has already seen this event; offsets are shrunk hard, so the effect is a few hundredths at most. Only skippers are rated.

  • u no fleet rating — the model's level for unrated skippers is the baseline.

Division A  7 boats · 5 races

FinSkipperSchool Races Rating
before
Perf.
rating
Δ Percentile
before → perf.
Surprise
(bits)
P(this good
or better)
Avg finish
actual / exp.
1Austen Freda '21Tufts University Jumbos 25/51.623.15+1.5392nd → 99th3.87%2.0 / 3.9
2Nathan Housberg '19Brown University5/51.782.32+0.5596th → 99th0.628%2.8 / 3.7
3William Colomb '18U. S. Coast Guard Academy Bears 15/51.58u2.39+0.8191st → 99th1.423%3.0 / 4.0
4Talia Toland '22Tufts University Jumbos 15/51.571.39−0.1791st → 88th0.149%3.8 / 3.9
5Amy Chamberlin '20U. S. Coast Guard Academy Bears 25/51.58u0.98−0.6091st → 73rd0.983%5.0 / 3.9
6Austin Brown '20U. S. Coast Guard Academy Bears 35/51.58u0.55−1.0391st → 53rd2.492%5.6 / 4.0
7Sophie Podlich '18University of Rhode Island5/51.020.82−0.2075th → 67th0.185%5.8 / 4.6

Conditions — 09/12/2017 (8am–6pm)

☁️Overcast
Humidity 57%  ·  Pressure 1015.0 hPa

Temperature

72°F
↑ 77°F   ↓ 61°F
Feels like 73°F

Wind

● from   ▲ toward
4.9 kn
avg  ·  max 7.6 kn
Gusts to 18.7 kn
From WSW (245°)

Sky & Precipitation

Cloud cover93% Sunshine10.1 hrs Humidity57% Pressure1015.0 hPa

What this breeze does at Coast Guard — from fleet racing

Breeze: SW about 8 kn (weather reanalysis in the scorer’s units)
In fleet races at Coast Guard in this breeze: a strongly underdogs’ day (−0.11)
Underdogs’ conditions: in fleet racing here the fleet bunches up and lower-rated boats beat the seeds more often than usual.

Orderliness is how tightly a fleet race’s finishing order follows the pre-regatta ratings, relative to a typical event (0): positive is the favourites’ day, negative the underdogs’. A value of ±0.11 means a rating gap counts about 9% less than on a typical day. This event is not a fleet race the rating model scores, so there is no actual value for it: this is what this venue’s fleet racing history says about the breeze on the day, read off the chart at the star. How this is estimated · compare venues.

Orderliness beyond the fleet at Coast Guard by wind direction (angle) and speed (rings), fitted surface; dots are labelled regatta-days, ★ this regatta (57 labelled fleet-race days at Coast Guard).

From the notes

Short write-ups of what the ratings and results show, with the numbers and how they were computed.

All notes →