Where a boat’s seconds went in each race, how places changed leg by leg, which side of each beat paid, and which measures moved with finishing place.
Seconds, part by part
Each leg time is compared with the fleet median on that leg. The start is the distance behind the leader 120 s after the gun, and turns are the number of tacks or gybes times the boat’s median clean-turn loss; both become seconds at the race’s median VMG on that point of sail. What remains of the beat and run differences is called beats and runs, so the parts add up to the race total.
Against another boat, the chart subtracts that boat’s budget from yours race by race. The regatta figure is the mean over the races where both have every leg, and the chart says how many that is.
Places on each leg
Places gained on a leg are the rank at its start minus the rank at its end. The first leg starts from the rank 60 s after the gun.
Which side paid
For each beat, Spearman’s ρ links each boat’s mean position across the course with the seconds it gained on the leader. With |ρ| under 0.35, or fewer than 4 boats, neither side is named.
What moved with finishing place
Each measure is ranked against finishing place inside each race and the race correlations are combined on Fisher’s z scale, so every race counts once. A strong link says the measure and the result moved together at this regatta. It does not say one caused the other.
The figures, one by one
Time budget
Each leg time against the fleet median on that leg, split into parts that sum to the total. The start is the distance behind the leader 120 s after the gun; tacks and gybes are the count of turns times the boat’s median clean-turn loss; both are turned into seconds at the race’s median VMG. Beats and runs are what remains of the leg-time differences, so they hold boatspeed, height, shifts, lanes and side together.
Unit
seconds per race
Reading it
+ is time lost, − is time gained, against the fleet median or the chosen boat.
Scope
Mean over the races where the boat (and benchmark) have every leg.
Rules this figure depends on, read from the analysis code
Rule
Value
Source
Start checkpoints after the gun
60 and 120 s
fleet-race.ts · START_CHECKPOINTS
Leg time kept, as multiples of the fleet median
0.75–1.5 ×
fleet-race.ts · LEG_DURATION_BOUNDS
Places gained on each leg
Rank at the end of the leg against rank at its start. The first leg starts from the rank 60 s after the gun.
Unit
places
Reading it
+ is places gained.
Scope
Per race and leg.
Rules this figure depends on, read from the analysis code
Rule
Value
Source
Start checkpoints after the gun
60 and 120 s
fleet-race.ts · START_CHECKPOINTS
Which side paid
Spearman’s ρ between each boat’s mean cross-course position on the beat and the seconds it gained on the leader across it. Below |ρ| 0.35 neither side is named, and at least 4 boats are needed.
Unit
rank correlation ρ; metres across the course; seconds gained
Reading it
Lateral + is right looking upwind; gain + is seconds gained on the leader against the fleet median.
Scope
Per beat.
Rules this figure depends on, read from the analysis code
Rule
Value
Source
Weakest correlation that names a side
0.35 ρ
fleet-regatta.ts · SIDE_PAID_MIN_RHO
Fewest boats for a rank correlation
4 boats
fleet-regatta.ts · SPEARMAN_MIN_PAIRS
What moved with finishing place
Spearman’s ρ between a measure and finishing place inside each race (at least 4 boats), averaged across races on Fisher’s z scale, so a breezy race and a light one each count once. It describes this regatta; it does not show cause.
Unit
rank correlation ρ
Reading it
Stronger links sit at the top; the sign says which way the measure ran with place.
Scope
Within each race, then combined across races.
Rules this figure depends on, read from the analysis code
Rule
Value
Source
Fewest boats for a rank correlation
4 boats
fleet-regatta.ts · SPEARMAN_MIN_PAIRS
Analysis version: fleet-race-4 · fleet-regatta-1.The numbers in this note are read from the same code that computes the figures, so they
change when it does.