Accuracy of Quoting Times and Handicap Values
Handicaps… (Of Trains & Boats & Aeroplanes)
Train time tables work in hours and minutes.
One could spend a year recording the exact time a particular train arrived at a station. It could recorded to the second or even 1/10 of a second. A sensible average time the train arrived could be computed, with a spread of times (variance) value.
But, in terms of a “predictor” i.e. something which indicates when the next train will arrive, then the average time including seconds is useless as the spread of times is just too great. So, train time tables work in hours and minutes – not seconds.
Aeroplanes have time tables to the minute. But such timetables are even less reliable as an accurate predictor of actual arrive times than those for trains.
(Sailing) Boats use a handicap as a predictor as to when they will finish relative to the rest of the fleet. A record a boat’s performance over many races can be used to create an average as a “predictor”. But experience shows that on a race by race basis, most boats fluctuate up and down around their allocated handicap by about +/-3%. Starting with a Time Correction Factor of 1.000 then +/- 3% affects the validity of the second decimal place.
To allow results to be separated a little more than 2 decimals permit, there is general world-wide consensus to use 3 decimals for Time-On-Time handicaps. This significantly “stretches” the validity of the predictability that such handicaps provide. To use 4 decimals stretches the validity of the maths tooooo far.
The accurately of the measured times is not the issue, nor is the number of time sampless that are averaged. The issue is the precision of that average as a predictor for future times.
- Finish Timing
- One Design Races
- Handicap Races.
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