# Binary independence condition

From Electowiki

**Binary independence** is a condition in Arrow's theorem.
A voting method F satisfies binary independence if and only if the
following condition holds; Let A and B be two candidates, and let p1 and p2 be
two profiles where each voter's preference for A vs. B in p1 agrees with her A vs. B
preference in p2. Then F gives the same A vs. B ranking for both p1 and p2.

The Binary Independence condition requires that in determining the A vs. B outcome, we cannot consider the voter's preferences for B vs. C or C vs. A.

Rated methods such as Approval voting and Range voting do satisfy binary independence.