Paper accepted at MIC’15

MIC15_logoThe paper “An Experimental Investigation of Reoptimization for Shift Scheduling” (Author: David Meignan) has been accepted as a full paper at the Metaheuristics International Conference 2015 (MIC’15). The paper presents the results of an experiment on interactive reoptimization.

Abstract: This paper presents an experimental study conducted with subjects on an interactive reoptimization method applied to a shift scheduling problem. The studied task is the adjustment, by a user, of candidate solutions provided by an optimization system in order to introduce a missing constraint. Two procedures are compared on this task. The first one is a manual adjustment of solutions assisted by a software that dynamically computes the cost of the current solution. The second procedure is based on reoptimization. For this procedure, the user defines some desired changes on a solution, and then a reoptimization method is applied to integrate the changes and reoptimize the rest of the solution. This process is iterated with additional desired changes until a satisfactory solution is obtained. For this interactive approach, the proposed reoptimization procedure is an iterated local search metaheuristic. The experiment, conducted with 16 subjects, provides a quantitative evaluation of the manual and reoptimization approaches. The results show that, even for small local adjustments, the manual modification of a solution has an important impact on the quality of the solution. In addition, the experiment demonstrates the efficiency of the interactive reoptimization approach and the adequacy of the iterated local search method for reoptimizing solutions. Finally, the experiment revealed some limitations of interactive reoptimization that are discussed in this article.

Visiting PhD student – DAAD Fellowship

daad_logo_smallCédric Boittin, PhD student at the UTBM (University of Technology of Belfort-Montbéliard), France, received a fellowship from the DAAD (Deutscher Akademischer Austaush Dienst) for a three months research stay at the University of Osnabrück, Germany. He will work on the topic of interactive optimization for simulation calibration, under the supervision of Dr. David Meignan, from February to April 2015. Fellowship program: DAAD Research grants – Short-term grants / DAAD Forschungsstipendien – Kurzstipendien.

Participants needed for usability experiment on interactive optimization

Update: The experiment is now complete and we are no longer searching for participants.

We are searching for student test-subjects for a usability experiment. The experiment is part of the DFG project “Interactive Metaheuristics” conducted at the Institute of Computer Science of the University of Osnabrück. Participants will have to perform simple optimization tasks with an interactive planning system. It will take about 2.5 hours and you will received a compensation of 7.5€ per hour. Two time slots are available: Wednesday 12 November starting at 13:00, and Friday 14 November starting at 13:00. The experiment will take place in building 69 on the Westerberg campus. Requirements: [1] Student at Uni. or FH Osnabrück, [2] average English reading skills (the software is in english), [3] familiar with computer software such as Word and Excel.

If you are interested or need more information, please contact Dr. David Meignan “meignan.david (et) gmail.com”.