Majority voting on orders

We characterize two lexicographic-type preference extension rules from a se t X to the set Psi of all orders on this set. Elements of X are interpreted as basic economic policy decisions, whereas elements of Psi are conceived as political programs among which a collectivity has to choose through majo rity voting. The main axiom is called tournament-consistency, and states th at whenever majority pairwise comparisons based on initial preferences on X define an order on X, then this order is also chosen by a majority among a ll other orders in Psi. Tournament-consistency thus allows to predict the o utcome of majority voting upon orders from the knowledge of majority prefer ences on their components.