Characterizing Global Minimizers of the Difference of Two Positive Valued Affine Increasing and Co-radiant Functions

Document Type : Research Paper


1 Mathematics, Mathematics and Computer Science, Shahid Bahonar University of Kerman, Kerman, Iran

2 Shahid Bahonar University of Kerman



‎Many optimization problems can be reduced to a
problem with an increasing and co-radiant objective function by a suitable transformation of variables. Functions, which are increasing and co-radiant, have found many applications in microeconomic analysis. In this paper, the abstract convexity of positive valued affine increasing and co-radiant (ICR) functions are discussed. Moreover, the basic properties of this class of functions such as support set, subdifferential and maximal elements of support set are characterized. Finally, as an application, necessary and sufficient conditions for the global minimum of the difference of two strictly positive valued affine ICR functions are presented.


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