On the Multi-Kind BahnCard Problem

The BahnCard problem is an important problem in the realm of online decision making. In its original form, there is one kind of BahnCard associated with a certain price, which upon purchase reduces the ticket price of train journeys for a certain factor over a certain period of time. The problem consists of deciding on which dates BahnCards should be purchased such that the overall cost, that is, BahnCard prices plus (reduced) ticket prices, is minimized without having knowledge about the number and prices of future journeys. In this paper, we extend the problem such that multiple kinds of BahnCards are available for purchase. We provide an optimal offline algorithm, as well as online strategies with provable competitiveness factors. Furthermore, we describe and implement several heuristic online strategies and compare their competitiveness in realistic scenarios

Strategic Decision Support for Smart-Leasing Infrastructure-as-a-Service

In this work we formulate strategic decision models describing when and how many reserved instances should be bought when outsourcing workload to an IaaS provider. Current IaaS providers offer various pricing options for leasing computing resources. When decision makers are faced with the choice and most importantly with uneven workloads, the decision at which time and with which type of computing resource to work is no longer trivial. We present case studies taken from the online services industry and present solution models to solve the various use case problems and compare them. Following a thorough numerical analysis using both real, as well as augmented workload traces in simulations, we found that it is cost efficient to (1) have a balanced portfolio of resource options and (2) avoiding commitments in the form of upfront payments when faced with uncertainty. Compared to a simple IaaS benchmark, this allows cutting costs by 20%

Transport Policy, Acceptance and the Media

The last two decades have seen a substantial change in the basic philosophy underlying European transportation policy. Due to the Commission's efforts and due to supporting jurisdiction by the European Court of Justice the dominant approach to transportation policy has become far more market oriented. This change of approach in transportation policy will only be successful and sustainable if the problem of acceptability will be solved. For researchers this entails that their perspective must change from the normative to the positive aspects of transportation policy-making. This paper reports work undertaken within research project TIPP (Transportation Institutions in the Policy Process) funded by the European Commission. In this work it has been attempted to develop a theoretical structure that merges the positive economic theory of regulation with cognitive psychology and traffic psychology. This theoretical structure offers a matrix of actors and factors that are seen to be essential for success or failure in the implementation of a certain measure of transport policy. Four case studies were carried out in order to check the plausibility of this approach. The case studies are the failure of the German Railway (Deutsche Bahn AG) to introduce a new tariff system in passenger transport in the period 2002-2003, the attempt to introduce a toll for HGVs in Germany, the failure to operate a private tolled motorway in Hungary (M1/M15), the failure to introduce a road-pricing system in the densely populated Randstad area in the Netherlands. --Transportation Policy,Europe,Common Transport Policy,Transport Regulation,Acceptability

Structural market changes and strategic adaptation along the value chain:theoretical perspectives and empirical evidence

Strukturelle Veränderungen der Wettbewerbslandschaft, insbesondere die Deregulierung von Märkten und der rasante technologische Fortschritt, nehmen Einfluss auf die optimale Gestaltung von Wertschöpfungsprozessen. Zwei wesentliche Trends sind beobachtbar: die zunehmende Desintegration von Produktionsprozessen und die Neuinterpretation der Rolle des Kunden im Wertschöpfungsprozess. Im Rahmen von drei empirischen und einer konzeptionellen Analyse werden wesentliche Implikationen für die erfolgreiche Gestaltung von Wertschöpfungsprozessen abgeleitet und erwartete Erfolgswirkungen struktureller Veränderungen entlang der Wertschöpfungskette kritisch reflektiert

Drivers of consumer behavior and competitive strategy outcomes:plurality of perspectives, modeling, and empirical evidence

Durch die rasante Entwicklung von Internet- und Telekommunikationstechnologien hat sich die Interaktion der Wettbewerbskräfte grundlegend verändert. Letztendlich kosteninduziert durch die IT-Entwicklung, erfährt das Customer Relationship Management (CRM) eine ständig wachsende Bedeutung für Unternehmensstrategie und Markterfolg. Ausgehend von der These, dass die gesteigerte Verbreitung von CRM-Strategien Unternehmen unterstützen kann, wertvolle und längerfristige Beziehungen zu Ihren Kunden zu etablieren, bedient diese Dissertation aktuelle Themen wie “Wachstum des e-Commerce”, “Bedeutung von CRM-Strategie, -Konzeption und -Performance” sowie “Evolution von Märkten”. Neben dem Wechsel von kunden- und firmengetriebener Sichtweise werden dabei interdisziplinäre Modellierungsansätze verwendet. Ergebnisse beinhalten konzeptionelle und strategische Implikationen hinsichtlich der effektiven Gestaltung von CRM-Prozessen und -Strategien und des Erfolges in zweiseitigen Märkten.In the course of the rapid development of Internet and telecommunication technologies the interaction of competitive forces has changed fundamentally. Eventually cost-induced by the IT-development, customer relationship management (CRM) has become increasingly important for business strategy and market success. Based on reasoning how the increased penetration of CRM philosophies and strategies in organizations can help to improve firms in establishing valuable long-term relationships with their customers, this thesis considers current issues as “growth of e-commerce”, “significance of CRM strategy, conception and performance” and “evolutionary market dynamics”. In this connection, customer- as well as firm-driven interdisciplinary modeling approaches are adopted. The findings bear conceptional and strategic implications for the effective design of CRM processes and strategies, and for the success in two-sided markets

The Multi-shop Ski Rental Problem

We consider the {\em multi-shop ski rental} problem. This problem generalizes the classic ski rental problem to a multi-shop setting, in which each shop has different prices for renting and purchasing a pair of skis, and a \emph{consumer} has to make decisions on when and where to buy. We are interested in the {\em optimal online (competitive-ratio minimizing) mixed strategy} from the consumer's perspective. For our problem in its basic form, we obtain exciting closed-form solutions and a linear time algorithm for computing them. We further demonstrate the generality of our approach by investigating three extensions of our basic problem, namely ones that consider costs incurred by entering a shop or switching to another shop. Our solutions to these problems suggest that the consumer must assign positive probability in \emph{exactly one} shop at any buying time. Our results apply to many real-world applications, ranging from cost management in \texttt{IaaS} cloud to scheduling in distributed computing

Demystifying the "Sunk Cost Fallacy": When Considering Fixed Cost in Decision-Making is Reasonable

Economic theory explains that when making decisions, historical costs should be irrelevant. When people are influenced by sunk costs in their decision-making, they are said to be committing the “sunk cost fallacy”, summarized by Kelly (2004) as the conjunction of two claims: (1) Individuals often do give weight to sunk costs in their decision-making, and (2) it is irrational for them to do so. Based on three studies both aspects are investigated (Amazons loyalty program Prime, German railways discount card BahnCard and decisions to use the own car when making long-haul trips). There are strong indicators that in all three examples fixed costs play a crucial role when consumers make decisions; and doing so is not necessarily irrational

Zum Lehren und Lernen von Phraseologismen im DaF-Studium. Überlegungen zu Inhalten und Methoden ihrer Vermittlung anhand eines Unterrichtsmodells

The contribution advocates a systematic inclusion of phraseology in university programs of the study of German as a Foreign Language. The author presents her own model of instruction that is based on a multimedial teaching and study material. The objective is to develop not only the students' linguistic competence, but also their metalinguistic awareness of phrasemes as a specific linguistic phenomenon. The author's aim is to give a theoretically well founded description of teaching processes focusing on a symbiosis of mediating linguistic as well as metalinguistic competence in the field of phraseology in German as a Foreign Language