Martin Josef Geiger

Publications (5)0 Total impact

• Article: On the assignment of students to topics: A Variable Neighborhood Search approach

  Martin Josef Geiger, Wolf Wenger
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  ABSTRACT: This article presents a study of a practical assignment problem found in teaching within higher education. Here, students are assigned to scientific topics for which written papers must be submitted. Often, preferences across topics exist among other side constraints that should be considered in solving the problem of interest. Characterizing attributes of real-world problems were studied for scientific departments in Economics and Business Administration at German universities by sending out 800 questionnaires, and analyzing the 203 responses. Based on earlier studies, a Variable Neighborhood Search (VNS) approach was formulated to solve the resulting assignment problem. Several neighborhood search operators were tested, and numerical results are reported for a range of problem scenarios taken from real-world cases. It was observed that VNS leads to superior results vs. single operator local search approaches. Furthermore, we were able to show that in the studied problem, the effectiveness of certain neighborhoods was, to a large extent, dependent on the structures of the underlying problem. An extension of the problem was formulated by integrating a second objective function, which simultaneously balances the workload of staff members while maximizing student utility. The VNS approach was implemented in a computer system, available free of charge, providing decision support for selected other institutions within higher education.
  Socio-Economic Planning Sciences 01/2010; 44(1):25-34.
• Source

  Available from: ArXiv

  Article: Variable Neighborhood Search for the University Lecturer-Student Assignment Problem

  Martin Josef Geiger, Wolf Wenger
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  ABSTRACT: The paper presents a study of local search heuristics in general and variable neighborhood search in particular for the resolution of an assignment problem studied in the practical work of universities. Here, students have to be assigned to scientific topics which are proposed and supported by members of staff. The problem involves the optimization under given preferences of students which may be expressed when applying for certain topics. It is possible to observe that variable neighborhood search leads to superior results for the tested problem instances. One instance is taken from an actual case, while others have been generated based on the real world data to support the analysis with a deeper analysis. An extension of the problem has been formulated by integrating a second objective function that simultaneously balances the workload of the members of staff while maximizing utility of the students. The algorithmic approach has been prototypically implemented in a computer system. One important aspect in this context is the application of the research work to problems of other scientific institutions, and therefore the provision of decision support functionalities.
  10/2008;
• Source

  Available from: ArXiv

  Article: A framework for the interactive resolution of multi-objective vehicle routing problems

  Martin Josef Geiger, Wolf Wenger
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  ABSTRACT: The article presents a framework for the resolution of rich vehicle routing problems which are difficult to address with standard optimization techniques. We use local search on the basis on variable neighborhood search for the construction of the solutions, but embed the techniques in a flexible framework that allows the consideration of complex side constraints of the problem such as time windows, multiple depots, heterogeneous fleets, and, in particular, multiple optimization criteria. In order to identify a compromise alternative that meets the requirements of the decision maker, an interactive procedure is integrated in the resolution of the problem, allowing the modification of the preference information articulated by the decision maker. The framework is prototypically implemented in a computer system. First results of test runs on multiple depot vehicle routing problems with time windows are reported.
  10/2008;
• Chapter: Market Based Allocation of Transportation Orders to Vehicles in Adaptive Multi-objective Vehicle Routing

  Martin Josef Geiger, Wolf Wenger
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  ABSTRACT: The article describes a study on vehicle routing problems under multiple objectives. In particular, we investigate the effectiveness of different approaches when assigning orders to vehicles. The resulting clustering problem is studied within a general framework for multi-objective vehicle routing problems where different vehicle agents place bids for orders which are offered on a marketplace. This marketplace gathers information about the current situation and provides the basis for the resolution of the allocation problem. By implementing different specialized but interacting software agents, an adaptation of the concept to various configurations of the studied problem is possible. Experimental investigations of different assignment logics on benchmark instances have been carried out and numerical results are reported. In brief, a tendency towards a particular clustering approach can be observed.
  06/2008: pages 119-132;
• Conference Proceeding: Ein Agentenbasiertes Konzept zur Interaktiven Lösung Multikriterieller Tourenplanungsprobleme.

  Wolf Wenger, Martin Josef Geiger
  INFORMATIK 2007: Informatik trifft Logistik. Band 1. Beiträge der 37. Jahrestagung der Gesellschaft für Informatik e.V. (GI), 24.-27. September 2007 in Bremen; 01/2007