A note on the query complexity of the Condorcet winner problem

Given an unknown tournament over {1,…,n}, we show that the query complexity of the question “Is there a vertex with outdegree n−1?” (known as a Condorcet winner in social choice theory) is exactly 2n−⌊log(n)⌋−2. This stands in stark contrast to the evasiveness of this property in general digraphs.