In this paper we consider the location of the eigenvalues of the composite matrix ( -A S1 S2 ) ( Q1 At 0 ) ( Q2 0 At ) , where the matrices Si and Qi are assumed to be semi-positive definite. Two interesting observations, which are not or only partially mentioned in literature before, challenge...

This note characterizes ordinal potential games by the absence of weak improvement cycles and an order condition on the strategy space.This order condition is automatically satisfied if the strategy space is countable.

AMS classification: 90D05;