The talk **Goal-oriented error estimation for elliptic optimal control problems**, by Professor Martin Weiser (Numerical Mathematics Department, Zuse Institute Berlin), will be held on Monday December 1, 2014 at 8:30 in room K4.

**Abstract of the talk**

Goal-oriented error estimation for PDE problems aims at estimating the error in a certain quantity of interest instead of some norm, and controls the mesh refinement process such as to create meshes adapted to this purpose. In optimal control problems, the natural quantity of interest is the objective. The talk highlights the difference between two seemingly similar formulations of the objective and discusses the impact on accuracy matching for inexact Newton methods. Hierarchical error estimators are proposed for computing the weight functions. Issues of global error transport in boundary control problems are considered. The concept is illustrated with several numerical examples.