Convex Directional Derivatives in Optimization
Abstract
Broadly speaking, a generalized convex function is one which has some property of convex functions that is essential in a particular application. Two such properties are convexity of lower level sets (in the case of quasiconvex functions) and convexity of the ordinary directional derivative as a function of direction (in the case of Pshenichnyi’s quasidifferentiable functions). In recent years, several directional derivatives have been defined that, remarkably, are always convex as a function of direction.
This means that all functions are “generalized convex” in the sense that they have certain convex directional derivatives. As a result, it has become worthwhile to develop generalizations of the Fritz John and Kuhn-Tucker optimality conditions in terms of the subgradients of convex directional derivatives. In this paper, we derive some general versions of these conditions for an inequality-constrained, nondifferentiable, nonconvex mathematical program.
Keywords
Maximal Element Directional Derivative Constraint Qualification Quasiconvex Function Calculus RulePreview
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References
- [1]Borvein J.M., Fractional programming without differentiability. Mathematical Programming 11 (1976) 283–290.Google Scholar
- [2]Borwein J.M., Stability and regular points of inequality systems. Journal of Optimization Theory and Applications 48 (1986) 9–52.Google Scholar
- [3]Borwein J.M.. Fitzpatrick S.P., and Giles J.R., The differentiability of real functions on normed linear Space using generalized subgradients. Journal of Mathematical Analysis and Applications 128 (1987) 512–534.CrossRefGoogle Scholar
- [4]Borwein J.M. and Strojwas H.M., Directionally Lipschitzian mapping on Baire spaces. Canadiana Journal of Mathematics 36 (1984) 95–130.Google Scholar
- [5]Caligaris O. and Oliva P., Necessary conditions for local Pareto minima. Bollettino della Unione Matematica Italiana 5-B (1986) 721 -750.Google Scholar
- [6]Clarke FJBL, A new approach to Lagrange multipliers. Mathematics of Operations Research 1 (1976) 165–174.Google Scholar
- [7]Clarke F.H., Optimization and nonsmooth analysis. John Wiley and Sons, New York, 1983.Google Scholar
- [8]Ekeland I. and Temam R., Convex analysis and variational problems. North- Holland, Amsterdam, 1976.Google Scholar
- [9]Hiriart-Urruty J.-B., On optimality conditions in nondifferentiable programming. Mathematical Programming 14 (1978) 73–86.Google Scholar
- [10]Hiriart-Urruty J.-B., New concepts in nondifferentiable programming. Bull. Soc. Math. France, Memoire 60 (1979) 57–85.Google Scholar
- [11]Ioffe A.D., Neressary condition for a local minimum. A reduction theorem and first-order conditions. STAM J.Cont. Opt. 17 (1979) 245–250.Google Scholar
- [12]Jeyakumar V., On optimality conditions in nonsmooth inequality-constrained minimization. Numerical Functional Analysis and Optimization 9 (1987) 535–546.Google Scholar
- [13]Merkovsky R.R. and Vard D.E., Upper D.S.L. approximates and nonsmooth optimization. preprint, 1988.Google Scholar
- [14]Michel P. and Penot J.-P., Calcul sous-differentiel pour des fonctions lipschitziennes et non lipschitziennes. C.R. Acad. Sci. Paris 298 (1984) 269–272.Google Scholar
- [15]Penot J.-P., Variations on the theme of nonsmooth analysis: another subdifferential. in: Demyanov V.F. and Pallaschke D., eds., Nondifferentiable optimization: motivations and applications, Springer-Verlag, Berlin, 1985, pp. 41–54.Google Scholar
- [16]Penot J.-P. and Terpolilli P., Cone tangents et singularites. C.R. Acad. Sci. Paris 296 (1983)721–724.Google Scholar
- [17]Pschenichnyi B.N., Necessary Conditions for an extremum. Marcel Dekker, New York, 1971.Google Scholar
- [18]Pschenichnyi B.N. and Khachatryan R.A., Constraints of equality type in nonsmooth optimization problems. Soviet Mathematics Doklady 26, (1982) 659–662.Google Scholar
- [19]Rockafellar R.T., Directionallv Lipschitzian functions and subdifferential calculus. Proceedings of the London Mathematical Society 39 (1979) 331–355.Google Scholar
- [20]Rockafellar R.T., Generalized directional derivative and subgradients of nonconve functions. Canadian Journal of Mathematics 32 (1980) 257–280.Google Scholar
- [21]Studniarski M., Mean value theorems and sufficient optimality conditions for nonsmooth functions. Journal of Mathematical Analysis and Applications 111(1985)313–326.Google Scholar
- [22]Ward D E., Convex subcones of the contingent cone in nonsmooth calculus and optimization. Transactions of the Américain Mathematical Society 302 (1987) 661–682.Google Scholar
- [23]Ward D.E., Directional derivative calculus and ootimalitv conditions in nonsmooth mathematical programming,to appear in Journal of Information and Optimization Sciences.Google Scholar
- [24]Ward D.B. and Borvein J.M., Nonsmooth callus in finite dimensions. SIAM J. Cont. Opt. 25 (1987) 1312–1340.Google Scholar