Characterizations of Nonsmooth Robustly Quasiconvex Functions

Abstract

© 2018, Springer Science+Business Media, LLC, part of Springer Nature. Two criteria for the robust quasiconvexity of lower semicontinuous functions are established in terms of Fréchet subdifferentials in Asplund spaces. The first criterion extends to such spaces a result established by Barron et al. (Discrete Contin Dyn Syst Ser B 17:1693–1706, 2012). The second criterion is totally new even if it is applied to lower semicontinuous functions on finite-dimensional spaces.