Some characterizations of functions generating K-Schur concave sums and of K-concave set-valued functions


In this note we establish some characterizations of (single valued) unctions, that assume values in a Banach space, generating K-Schur concave sums. These results improve some theorems obtained in [13] and [11]. Moreover we prove that a set-valued function is K-concave if and only of it is K-t-concave and K-quasi concave (where t is a fixed number in (0,1)). This result improves the theorems obtained in [11], [2], [5] and extends the theorem of [3].

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Published : 1995-09-29

CardinaliT. (1995). Some characterizations of functions generating K-Schur concave sums and of K-concave set-valued functions. Annales Mathematicae Silesianae, 9, 17-28. Retrieved from

Tiziana Cardinali 
Department of Mathematics, Perugia University, Italy  Italy

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