Ralph Schäfer

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Evaluation-oriented information provision is a function performed by many systems that serve as personal assistants, advisors, or sales assistants. Five general tasks are distinguished which need to be addressed by such systems. For each task, techniques employed in a sample of systems are discussed, and it is shown how the lessons learned from these(More)
THE CONFIGURATION OF PRODUCTS AND SERVICES WITH MULTIPLE SUPPLIERS (CAWICOMS) aims at the next generation of web-based configuration applications that cope with two challenges of today’s open, networked economy: (1) the support for heterogeneous user groups in an open-market environment and (2) the integration of configurable subproducts provided by(More)
Bayesian networks have been successfully applied to the assessment of user properties which remain unchanged during a session. However, many properties of a person vary over time, thus raising new questions of network modeling. In this paperwe characterize different types of dependencies that occur in networks that deal with the modeling of temporally(More)
The modeling of noncooperative dialogs, as opposed to dialogs in which the goals of the participants coincide, presents novel challenges to a pragmatically oriented dialog system. PRACMA models noncooperative sales dialogs. In the role of the potential buyer of a used car, the system tries to arrive at a realistic evaluation of the unknown car in spite of(More)
This paper presents a description of AXIOLOGIS, a component of the natural-language dialog system PRACMA. AXIOLOGIS can be used to arrive at an overall evaluation of an object with unknown attributes by using a Bayesian network. For this evaluation, the attributes of the object are clustered into groups which are evaluated separately to yield intermediate(More)
Im vorliegenden Anwendungsbeitrag berichten wir über eine Projektkooperation zwischen der Daimler-Benz Forschung, Berlin und der DFKI GmbH. Ziel dieser Kooperation war die Entwicklung eines Ansatzes zur Online-Erstellung individueller Kundenprofile auf elektronischen Marktplätzen, um den potentiellen Kunden bei der Suche und Auswahl von Produkten zu(More)
In this paper, we describe the use of a hierarchical ontology representation as a basis for modelling user preferences in the SAID project for elderly and disabled persons. The nodes of the ontology tree are associated with either pre-selected or dynamically found web sites relevant for each topic of the user’s interest (in this way web-surfing can be(More)
Recent advances in user modeling technology have brought within reach the goal of having systems adapt to temporary limitations of the user’s available time and working memory capacity. We first summarize empirical research by ourselves and others that sheds light on the causes and consequences of these (continually changing) resource limitations. We then(More)