J70 Tuesday Series #4

# SchoolTeam A TOT
1 U. S. Coast Guard Academy U. S. Coast Guard Academy Bears 1 8 8
2 U. S. Coast Guard Academy U. S. Coast Guard Academy Bears 2 12 12
3 University of Rhode Island University of Rhode Island Rams 12 12
4 U. S. Coast Guard Academy U. S. Coast Guard Academy Bears 3 14 14
5 U. S. Coast Guard Academy U. S. Coast Guard Academy Bears 4 18 18
6 U. S. Coast Guard Academy U. S. Coast Guard Academy Bears 5 20 20
7 U. S. Coast Guard Academy U. S. Coast Guard Academy Bears 6 28 28
SchoolTeam R1 R2 R3 R4 TOT
U. S. Coast Guard Academy U. S. Coast Guard Academy Bears 1 5 1 1 1 8
U. S. Coast Guard Academy U. S. Coast Guard Academy Bears 2 1 2 5 4 12
University of Rhode Island University of Rhode Island Rams 3 4 2 3 12
U. S. Coast Guard Academy U. S. Coast Guard Academy Bears 3 2 6 4 2 14
U. S. Coast Guard Academy U. S. Coast Guard Academy Bears 4 6 3 3 6 18
U. S. Coast Guard Academy U. S. Coast Guard Academy Bears 5 4 5 6 5 20
U. S. Coast Guard Academy U. S. Coast Guard Academy Bears 6 7 7 7 7 28

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.
  • — in the performance column: last in every race sailed, so no finite least-surprisal rating exists.

Division A  7 boats · 4 races

FinSkipperSchool Races Rating
before
Perf.
rating
Δ Percentile
before → perf.
Surprise
(bits)
P(this good
or better)
Avg finish
actual / exp.
1Andrew Goetz '18U. S. Coast Guard Academy Bears 14/41.58u2.90+1.3291st → 99th2.36%2.0 / 3.8
2Richard O'Leary '21U. S. Coast Guard Academy Bears 24/41.58u2.20+0.6391st → 99th0.729%3.0 / 3.8
2Sophie Podlich '18University of Rhode Island4/41.022.37+1.3575th → 99th2.915%3.0 / 4.5
4William Colomb '18U. S. Coast Guard Academy Bears 34/41.58u1.87+0.2991st → 97th0.246%3.5 / 3.8
5Eric Gimple '20U. S. Coast Guard Academy Bears 44/41.031.46+0.4475th → 89th0.452%4.5 / 4.5
6Amy Chamberlin '20U. S. Coast Guard Academy Bears 54/41.58u1.28−0.3091st → 85th0.284%5.0 / 3.8
7Austin Brown '20U. S. Coast Guard Academy Bears 64/41.58u——91st → —13.1>99%7.0 / 3.8

Conditions — 10/03/2017 (8am–6pm)

☀️Clear sky
Humidity 65%  ·  Pressure 1036.7 hPa

Temperature

61°F
↑ 64°F   ↓ 55°F
Feels like 58°F

Wind

● from   ▲ toward
5.5 kn
avg  ·  max 7.0 kn
Gusts to 18.7 kn
From SE (131°)

Sky & Precipitation

Cloud cover40% Sunshine11.0 hrs Humidity65% Pressure1036.7 hPa

What this breeze does at Coast Guard — from fleet racing

Breeze: SE about 8 kn (weather reanalysis in the scorer’s units)
In fleet races at Coast Guard in this breeze: an underdogs’ day (−0.02)
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 ±0.02 means a rating gap counts about 2% 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 →