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Published equation contexts

P(A≻B)=11+10−(RA−RB)/400P(A \succ B) = \frac{1}{1 + 10^{-(R_A - R_B)/400}}

Why this formula appears here

The response, arriving in 2023, was to stop checking against a fixed answer and start recording a preference between two outputs instead. Chatbot Arena built an open platform in which users submit a prompt, receive responses from two anonymized models side by side, and vote for the one they prefer, without knowing which model produced which response; its authors reported collecting more than 240,000 such votes from a broad user base and validated that crowdsourced preferences agreed well with those of a separate panel of expert raters [ 12 ] . Pairwise votes of this kind are naturally converted into a single continuous rating using a Bradley–Terry-style model — the same functional form used…

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AA

Symbol A

A occurs below the fraction bar. The quantity above the bar is divided by this expression; zero is excluded as a denominator.

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RAR_A

Symbol R_A

RAR_A occurs below the fraction bar. The quantity above the bar is divided by this expression; zero is excluded as a denominator.

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RBR_B

Symbol R_B

RBR_B occurs below the fraction bar. The quantity above the bar is divided by this expression; zero is excluded as a denominator.

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1+10−(RA−RB)/4001 + 10^{-(R_A - R_B)/400}

Denominator: 1 + 10^-(R_A - R_B)/400

The complete quantity below the fraction bar; it must be nonzero for this division.

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How to interpret it

With a fixed numerator, increasing a nonzero denominator reduces the fraction. Read it with the definitions, units, and assumptions supplied by the article.

Research cited beside this formula

Published contexts (1)

A symbol can carry a different meaning in another article. Each occurrence keeps its own guide and term definitions.

P(A≻B)=11+10−(RA−RB)/400.P(A \succ B) = \frac{1}{1 + 10^{-(R_A - R_B)/400}}.

Equation 6 · Model Evaluation

From Origins to Frontier: A History of Frontier AI Model Comparisons

This equation states an equality: the expressions on both sides have the same value under the article’s assumptions.

The response, arriving in 2023, was to stop checking against a fixed answer and start recording a preference between two outputs instead. Chatbot Arena built an open platform in which users submit a prompt, receive responses from two anonymized models side by side, and vote for the one they prefer, without knowing which model produced which response; its authors reported collecting more than 240,000 such votes from a broad user base and validated that crowdsourced preferences agreed well with those of a separate panel of expert raters [ 12 ] . Pairwise votes of this kind are naturally converted into a single continuous rating using a Bradley–Terry-style model — the same functional form used…

Meanings in this article

  • BB: modeled as a logistic function of the difference between two scalar ratings: [displayed formula].
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