User modeling

About: User modeling is a research topic. Over the lifetime, 10701 publications have been published within this topic receiving 278012 citations.

Improving ontology-based user profiles

Abstract: Personalized Web browsing and search hope to provide Web information that matches a user's personal interests and thus provide more effective and efficient information access. A key feature in developing successful personalized Web applications is to build user profiles that accurately represent a user's interests. The main goal of this research is to investigate techniques that implicitly build ontology-based user profiles. We build the profiles without user interaction, automatically monitoring the user's browsing habits. After building the initial profile from visited Web pages, we investigate techniques to improve the accuracy of the user profile. In particular, we focus on how quickly we can achieve profile stability, how to identify the most important concepts, the effect of depth in the concept-hierarchy on the importance of a concept, and how many levels from the hierarchy should be used to represent the user. Our major findings are that ranking the concepts in the profiles by number of documents assigned to them rather than by accumulated weights provides better profile accuracy. We are also able to identify stable concepts in the profile, thus allowing us to detect long-term user interests. We found that the accuracy of concept detection decreases as we descend them in the concept hierarchy, however this loss of accuracy must be balanced against the detailed view of the user available only through the inclusion of lower-level concepts.

The user–developer communication process: a critical case study

Abstract: .Although user participation in systems development is widely believed to have positive impacts on user acceptance, it does not guarantee success and there is still much that we do not know about how and why user participation sometimes delivers positive benefits, but not always. Much of the prior research on user participation assumes that user–developer communication will ensure that the resulting system will be designed to meet users’ needs and will be accepted by them. The nature and quality of the communication between users and developers, however, remains an understudied aspect of user participation. In this paper, we focus on the user–developer communication process. We propose a process model that delineates four stages of communication between users and software developers, and we argue that these stages must occur for user participation to lead to effective outcomes. To illustrate our model, we apply it to analyse a ‘critical case study’ of a software project that failed despite high levels of user involvement. We show that when ‘communication lapses’ occurred in several of the user–developer communication stages, developers failed to be informed regarding the underlying reasons that users avoided the system. Based on the insights from this case study, we advise researchers and practitioners how to leverage the potential benefits of user participation, rather than take them for granted.

A multilevel approach to intelligent information filtering: model, system, and evaluation

Abstract: In information-filtering environments, uncertainties associated with changing interests of the user and the dynamic document stream must be handled efficiently. In this article, a filtering model is proposed that decomposes the overall task into subsystem functionalities and highlights the need for multiple adaptation techniques to cope with uncertainties. A filtering system, SIFTER, has been implemented based on the model, using established techniques in information retrieval and artificial intelligence. These techniques include document representation by a vector-space model, document classification by unsupervised learning, and user modeling by reinforcement learning. The system can filter information based on content and a user's specific interests. The user's interests are automatically learned with only limited user intervention in the form of optional relevance feedback for documents. We also describe experimental studies conducted with SIFTER to filter computer and information science documents collected from the Internet and commercial database services. The experimental results demonstrate that the system performs very well in filtering documents in a realistic problem setting.

I Like It... I Like It Not: Evaluating User Ratings Noise in Recommender Systems

Abstract: Recent growing interest in predicting and influencing consumer behavior has generated a parallel increase in research efforts on Recommender Systems. Many of the state-of-the-art Recommender Systems algorithms rely on obtaining user ratings in order to later predict unknown ratings. An underlying assumption in this approach is that the user ratings can be treated as ground truth of the user's taste. However, users are inconsistent in giving their feedback, thus introducing an unknown amount of noise that challenges the validity of this assumption. In this paper, we tackle the problem of analyzing and characterizing the noise in user feedback through ratings of movies. We present a user study aimed at quantifying the noise in user ratings that is due to inconsistencies. We measure RMSE values that range from 0.557 to 0.8156. We also analyze how factors such as item sorting and time of rating affect this noise.

Universal Access in the Information Society: Methods, Tools, and Interaction Technologies

Abstract: Accessibility and high quality of interaction with products, applications, and services by anyone, anywhere, and at any time are fundamental requirements for universal access in the emerging Information Society. This paper discusses these requirements, and their relation to the concept of automated adaptation of user interfaces. An example application is presented, showing how adaptation can be used to accommodate the requirements of different user categories and contexts of use. This application is then used as a vehicle for discussing a new engineering paradigm appropriate for the development of adaptation-based user interfaces. Finally, the paper investigates issues concerning the interaction technologies required for universal access.