This paper contributes to the axiomatization of additive rules for ranking sets of objects under the psychological principle of categorization. Firstly we proceed with the case where the elements in the sets are categorized into at most three groups, namely good (with value 1), neutral (with...

I study a market model in which profit-maximizing firms compete in multi-dimensional pricing strategies over a consumer, who is limited in his ability to grasp such complicated objects and therefore uses a sampling procedure to evaluate them. Firms respond to increased competition with an...