Rust (1987) concludes that the data "clearly reject" the hypothesis that Harold Zurcher made bus replacement decisions using a monthly (and myopic) discount rate of 0 in favor of the factor 0.9999. The alternative model requires the nested fixed point algorithm developed in the paper which...

The elastic generalized assignment problem (eGAP) is a natural extension of the generalized assignment problem (GAP) where the capacities are not fixed but can be adjusted which is expressed by continuous variables. These variables might be un-bounded or restricted by a lower or upper bound,...

The elastic generalized assignment problem (eGAP) is a natural extension of the generalized assignment problem (GAP) where the capacities are not any longer fixed but can be adjusted which is expressed by continuous variables. These variables might be unbounded or restricted by a lower or upper...

Die Erfahrungen aus der jüngsten Finanzmarktkrise zeigen, dass der gezielten Abschätzung und Steuerung von Kreditrisiken in Banken eine enorme betriebs- und volkswirtschaftliche Bedeutung zukommt. Sowohl in der internen Kreditrisikomessung als auch bei den zugehörigen gesetzlichen Vorgaben...

Resource-constrained project scheduling under a net present value objective attracts growing interest. Because this is an NP-hard problem, it is unlikely that optimum solutions can be computed for large instances. Thus, heuristics have become a popular research field. Up to now, however, tight...

This paper introduces a new general framework for genetic algorithms to solve a broad range of optimization problems. When designing a genetic algorithm, there may be several alternatives for a component such as crossover, mutation or decoding procedure, and it may be difficult to determine the...

The sales force deployment problem is considered which arises in many selling organizations. As a solution a novel mixed-integer formulation is introduced which is specifically characterized by an infinite number of variables. A column generation approach is proposed to obtain upper and lower...

In der vorliegenden Untersuchung wird die operative Entscheidung über Eigenfertigung und Fremdbezug betrachtet. Exemplarisch wird dargelegt, dass klassische Entscheidungshilfen unwirtschaftliche Ergebnisse hervorbringen. Die qualitative und quantitative Fehlspezifikation der Fremdbezugsprodukte...

On a very abstract level, an information system consists of a set of system elements which communicate with each other. Communication is an unproductive operation, so the time needed to communicate data should be kept as short as possible and, to put it in monetary terms, the opportunity costs...

The Capacitated Facility Location Problem (CFLP) is a well-known combinatorial optimization problem with applications in distribution and production planning. A variety of lower bounds based on Lagrangean relaxation and subgradient optimization has been proposed for this problem. However, in...