David Hoornstra - FencingTracker

Ann Arbor Dueling Society

Weapon	Type	Strength	Estimate Range^*	Min	Max
Épée	DE	1785	1021 - 2548	1785	2240
Épée	Pool	2110	1774 - 2445	1988	2134
Foil	DE	2510	1243 - 3776	2510	2510
Foil	Pool	1875	1125 - 2624	1875	1875
Saber	DE	2162	794 - 3529	2162	2162
Saber	Pool	1353	718 - 1987	1353	1353

^* We're quite confident that the person's true strength is somewhere between those numbers. For those statistically inclined, it is a 95% confidence interval of the estimate (i.e., μ ± 2σ).

Matchup against me

Outcome	Chance	My strength change	Their strength change
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Strength over time

The strength changes are summaries from all events of that day. The dotted line indicates that the strength rating is too uncertain.

Explanation

The strength number is a numeric representation of how a fencer has performed against others historically.

The system "learns" your strength as you fence. It takes about 12 bouts for it to zero in on a good estimate. This is why in the beginning you will often see wild fluctuations.

An unknown fencer starts with a 2500 strength, but with very high uncertainty.

Due to their different natures, pools, direct elimination, and mixed gender bouts are tracked separately.

The lowest possible is zero, average is around 2500, highest possible is around 5000. The scale is not linear, which means that higher numbers are increasingly harder to obtain. To be precise, the distribution of strength numbers looks like a bell curve.

If you beat a much stronger fencer, your strength will go up by a lot. If you beat a much weaker fencer, your strength will go up by little or maybe even not at all. Losses follow the same logic. You can see detailed changes after each bout in the bout history.

Probability of winning doesn't account for difference in fencing styles, familiarity with opponents, or any of such things. It is a reflection of the difference in strength estimates assuming that both of you perform just like you did against others in the past.