We compare the Fenchel-Moreau second conjugates associated to an arbitrary coupling function φ:X×W→R‾=[−∞,+∞]\varphi:X\times W\rightarrow \overline{R}=[-\infty,+\infty ] between two sets XX and WW with the second level set conjugates associated to the same coupling. For a coupling φ:Rn×Rn→R=(−∞,+∞)\varphi:R^{n}\times R^{n}\rightarrow R=(-\infty,+\infty ) that is additively homogeneous in one (or both) of the variables we also compare the first conjugates associated to the same coupling. We give an application to the ``min-type'' coupling function arising in the study of topical functions.

Contact details are reproduced from the original publication and may be historical.

Juan-Enrique Martínez-Legaz

Dep. d'Economia i d'Història Econòmica, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain

Ivan Singer

Institute of Mathematics, P.O. Box 1-764, 70700 Bucharest, Romania

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J.-E. Martínez-Legaz, I. Singer. “Comparing Fenchel-Moreau Conjugates with Level Set Conjugates.” Journal of Convex Analysis 15 (2008), No. 2, 285–297. https://doi.org/10.68381/jca15020