This paper contributes to the elicitation of a decision maker's strict preferences and their possible indifference or incomparability/indecisiveness. Every subject in both treatments of an incentivized lab experiment could choose multiple alternatives from each of the 50 distinct menus of...

Two logically distinct and permissive extensions of iterative weak dominance are introduced for games with possibly vector-valued payoffs. The first, iterative partial dominance, builds on an easy-to-check condition but may lead to solutions that do not include any (generalized) Nash equilibria....

This paper proposes a model of choice that does not assume completeness of the decision maker's preferences. The model explains in a natural way, and within a unied framework of choice when preference-incomparable options are present, four behavioural phenomena: the attraction effect, choice...

We report on two novel choice experiments with real goods where subjects in one treatment are forced to choose, as is the norm in economic experiments, while in the other they are not but can instead incur a small cost to defer choice. Using a variety of measures, we find that the active choices...

A weak (strict) preference relation is continuous if it has a closed (open) graph; it is hemicontinuous if its upper and lower contour sets are closed (open). If preferences are complete these four conditions are equivalent. Without completeness continuity in each case is stronger than...

Sufficient conditions are provided for a possibly incomplete preference preorder on a topological space to be closed in the product space if and only if it has closed upper and lower contour sets. Notably, it is shown that the two properties are equivalent if the domain of the preorder is a...