Interacting with a recommender system means to take different decisions such as selecting a song/movie from a recommendation list, selecting specific feature values (e.g., camera's size, zoom) as criteria, selecting feedback features to be critiqued in a critiquing based recommendation session, or selecting a repair proposal for inconsistent user preferences when interacting with a knowledge-based recommender. In all these scenarios, users have to solve a decision task. The major focuses of this workshop ([email protected]) were approaches for efficient human decision making in different types of recommendation scenarios.

Constraint sets can become inconsistent in different contexts. We are interested in identifying minimal sets of constraints that have to be adapted or deleted in order to restore consistency. In this paper we sketch a highly efficient divide-and-conquer based diagnosis approach which identifies minimal sets of faulty constraints in a given over-constrained problem. This approach is specifically applicable in scenarios where the efficient identification of leading (preferred) diagnoses is crucial.

Configuration technologies are well established as a foundation of mass customization which is a production paradigm that supports the manufacturing of highly-variant products under pricing conditions similar to mass production. A side-effect of the high diversity of products offered by a configurator is that the complexity of the alternatives may outstrip a user's capability to explore them and make a buying decision. In order to improve the quality of configuration processes, we combine knowledge-based configuration with collaborative and content-based recommendation algorithms. In this paper we present configuration techniques that recommend personalized default values to users. Results of an empirical study show improvements in terms of, for example, user satisfaction or the quality of the configuration process.