Definition

A competitor set is the list of brands you consider alternatives to yours. In AI measurement it should be an input for reporting, never the filter that decides which brands get counted in an answer.

Why it matters

Buyers are shown whatever the assistant names, including brands you have never heard of. Counting only your list makes the market look smaller and your position stronger than either really is.

How to measure it

Count every brand the answers name, then use your list only to highlight rows. Review the unlisted brands that keep appearing; they are the competitor set the market actually has.