activity
20172022
collaborators

10 papers

math.OC2022

Duality theory for optimistic bilevel optimization

Houria En-Naciri, Lahoussine Lafhim, Alain Zemkoho

In this paper, we exploit the so-called value function reformulation of the bilevel optimization problem to develop duality results for the problem. Our approach builds on Fenchel-…

math.OC2021

Levenberg-Marquardt method and partial exact penalty parameter selection in bilevel optimization

Andrey Tin, Alain B. Zemkoho

We consider the optimistic bilevel optimization problem, known to have a wide range of applications in engineering, that we transform into a single-level optimization problem by me…

math.OC2020

Newton-type method for bilevel programs with linear lower level problem and application to toll optimization

Floriane Mefo Kue, Thorsten Raasch, Alain B. Zemkoho

We consider a bilevel program involving a linear lower level problem with left-hand-side perturbation. We then consider the Karush-Kuhn-Tucker reformulation of the problem and subs…

math.OC2020

Theoretical and numerical comparison of the Karush-Kuhn-Tucker and value function reformulations in bilevel optimization

Alain Zemkoho, Shenglong Zhou

The Karush-Kuhn-Tucker and value function (lower-level value function, to be precise) reformulations are the most common single-level transformations of the bilevel optimization pr…

math.OC2019

Semismooth Newton-type method for bilevel optimization: Global convergence and extensive numerical experiments

Andreas Fischer, Alain B. Zemkoho, Shenglong Zhou

We consider the standard optimistic bilevel optimization problem, in particular upper- and lower-level constraints can be coupled. By means of the lower-level value function, the p…

math.OC2019

Sufficient optimality conditions in bilevel programming

Patrick Mehlitz, Alain B. Zemkoho

This paper is concerned with the derivation of first- and second-order sufficient optimality conditions for optimistic bilevel optimization problems involving smooth functions. Fir…