A product set of pure strategies is a prep set ("prep" is short for "preparation") if it contains at least one best reply to any consistent belief that a player may have about the strategic behavior of his opponents. Minimal prep sets are shown to exists in a class of strategic games satisfying...

The Pareto dominance relation is shown to be the unique nontrivial partial order on the set of finite-dimensional real vectors satisfying a number of intuitive properties. -- Pareto dominance ; characterization