Robert O'Brien

Career: 56.90 percentile of ICSA crews (limited evidence)

▲ boats did better with this crew than with the skipper's usual crews▼ worseArrow length = size of the push, in rating points

Season	Team	Rating	Range	League percentile	Team percentile	On team	Races	Team page
Fall 2026	University of Michigan	1.67		57.32	45.00	6 of 10	13	Team page

Regatta	Role	Div	Races	Avg	Rating
Fall 2026 Team page Season
David Lee Arnoff	Crew	A	13	11.6	+0.31
Acton Up 2026	Skipper	B	6	2.7	0.38

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

How do skipper ratings work?A log-strength fitted to every race at once, smoothed week to week.
What a rating point is worthA one-point edge is a 73% chance to beat another boat in a race; two points is 88%.
How does a crew rating work?A crew rating is small and uncertain; a worked example on one roster.