We characterize the following choice procedure. The decision maker is endowed with a preference and a similarity - a reflexive binary relation over alternatives. In any choice problem she includes in her choice set all options that are similar to her most preferred feasible alternative. Hence an...

Classical deÖnitions of complementarity are based on cross price elasticities, and so they do not apply, for example, when goods are free. This context includes many relevant cases such as online newspapers and public attractions. We look for a complementarity notion that does not rely on price...

We study a class of boundedly rational choice functions, namely two-stage choosers, which operate as follows. The decision maker uses two criteria in two stages to make a choice. First she shortlists the top-2 alternatives, i.e. two ?nalists, according to one criterion. Next, she chooses the...