We consider a class of functions satisfying the gross-substitution property (GS-functions). We show that GS-functions are concave functions whose parquets are constributed by quasi-polymatroids. The class of conjugate functions to GS-functions turns out to be the class of polyhedral supermodular...

We consider a two-sided buyers & sellers' market with indiviseble goods. Agents may trade many units of any of the items available. Previous research, documenting the case ofunit-flow trades, showed that the existence of substitutability or complementarity colligations between goods. These...

Random sets might be considered from several possible viewpoints. A "Business-managerial" 'viewpoint' would prop the following definition : take all sets, list them and then pick one set from this list at random. An "Image analysis" 'viewp oint' would yield alternatively the following...