Hypermedia applications offer users the impression that there are many meaningful ways to navigate through a large body of information nodes. This rich link structure not only creates orientation problems, it may also be a source of comprehension problems when users follow paths through the information which the author did not foresee. Adaptive techniques have been used by a number of researchers [1, 2, 4, 5, 6, 7, 8, 9, 10, 17, 19, 20, 22] in an attempt to offer guidance through and orientation support for rich link structures. The majority of these adaptive hypermedia systems (AHS) have been used in educational applications. The terminology used in this paper also has an educational "flavor". However, there are some adaptive on-line information systems (or "kiosk"- systems), adaptive information retrieval systems, and other adaptive hypermedia applications. In this paper we describe a reference model for adaptive hypermedia applications, called AHAM, which encompasses most features...

Abstract: This paper discusses the problems of developing versatile adaptive and intelligent learning systems that can be used in the context of practical Web-based education. We argue that versatility is an important feature of successful Web-based education systems. We introduce ELM-ART, an intelligent interactive educational system to support learning programming in LISP. ELM-ART provides all learning material online in the form of an adaptive interactive textbook. Using a combination of an overlay model and an episodic student model, ELM-ART provides adaptive navigation support, course sequencing, individualized diagnosis of student solutions, and example-based problem-solving support. Results of an empirical study show different effects of these techniques on different types of users during the first lessons of the programming course. ELM-ART demonstrates how some interactive and adaptive educational components can be implemented in WWW context and how multiple components can be naturally integrated together in a single system.

. We describe the user modeling and personalization techniques adopted in SETA, a prototype toolkit for the construction of adaptive Web stores which customize the interaction with users. The Web stores created using SETA suggest the items best fitting the customers' needs and adapt the layout and the description of the store catalog to their preferences and expertise. SETA uses stereotypical information to handle the user models and applies personalization rules to dynamically generate the hypertextual pages presenting products. The system adapts the graphical aspect, length and terminology used in the descriptions to parameters like the user's receptivity, expertise and interests. Moreover, it maintains a model associated with each person the goods are selected for; in this way, multiple criteria can be applied for tailoring the selection of items to the preferences of their beneficiaries. Keywords: user modeling, personalized information presentation, customization of Web stores, ...

Abstract. We describe the user modeling and personalization techniques adopted in SETA, a shell supporting the construction of adaptive Web stores which customize the interactions with users, suggesting the items best fitting their needs, and adapting the description of the store catalog to their preferences and expertise. SETA uses stereotypical information to handle the user models and applies personalization rules to dynamically generate the hypertextual pages presenting products: the system adapts the graphical aspect, length and terminology used in the descriptions to the user’s receptivity, expertise and interests. Moreover, it maintains a profile associated to each person the goods are selected for, to provide multiple criteria for the selection of items, tailored to the beneficiaries ’ preferences. 1

With the recent expansion of the Internet, the interest towards electronic sales has quickly grown and many tools have been built to help vendors to set up their Web stores. These tools offer all the facilities for building the store databases and managing the order processing and secure payment transactions, but they typically do not focus on issues like the personalization of the interaction with the customers. However, Web surfers are generally heterogeneous and have different needs and preferences; moreover, the trend of marketing strategies is to pay more and more attention to the specific buyers. So, the importance of personalizing the interaction with the user and the product presentation is increasing. In this paper, we describe the architecture of a configurable virtual Web store supporting personalized hypertextual interactions with users. Our system builds a user profile by applying user modeling techniques and stereotypical information about the characteristics of customer groups; this profile is used during the interaction in order to tailor the product descriptions and the selection of items to recommend to the user's needs, varying the layout of the hypertextual pages and the detail of the descriptions accordingly. Tailoring the system's behavior requires the parallel execution of several complex tasks during the interaction (e.g. identifying the user's preferences, selecting the products most suited to her, dynamically generating the hypertextual pages). Therefore, we have defined a multiagent architecture where these tasks

This paper presents the principles of ontology-supported and ontology-driven conceptual navigation. Conceptual navigation realizes the independence between resources and links to facilitate interoperability and reusability. An engine builds dynamic links, assembles resources under an argumentative scheme and allows optimization with a possible constraint, such as the user’s available time. Among several strategies, two are discussed in detail with examples of applications. On the one hand, conceptual specifications for linking and assembling are embedded in the resource meta-description with the support of the ontology of the domain to facilitate meta-communication. Resources are like agents looking for conceptual acquaintances with intention. On the other hand, the domain ontology and an argumentative ontology drive the linking and assembling strategies.

This paper provides an overall presentation of the M-PIRO project. M-PIRO is developing technology that will allow museums to generate automatically textual or spoken descriptions of exhibits for collections available over the Web or in virtual reality environments. The descriptions are generated in several languages from information in a language-independent database and small fragments of text, and they can be tailored according to the backgrounds of the users, their ages, and their previous interaction with the system. An authoring tool allows museum curators to update the system's database and to control the language and content of the resulting descriptions. Although the project is still in progress, a Web-based demonstrator that supports English, Greek and Italian is already available, and it is used throughout the paper to highlight the capabilities of the emerging technology.

. With the increasing popularity of Web shopping, the personalization of the front-end of on-line stores has become a critical issue: these systems are accessed by customers with different backgrounds, expertise and preferences; therefore, their usability can only be improved by personalizing their interfaces to the needs of each specific user. In this paper, we describe the architecture of SETA, a prototype toolkit for the creation of adaptive Web stores, where user modeling and flexible hypermedia techniques are exploited to personalize the interaction with the user, dynamically generating the catalog pages on the basis of the user's features. The SETA architecture is composed by different specialized agents, which cooperate to the management of the interaction with the user; we will discuss how the application of agent-based techniques has been essential to the design and development of this system. 1 Introduction The research on electronic commerce has opened several ...

The undi erentiated approach to mass marketing has been recently replaced with market segmentation techniques: psychographic and socio-demographic analyses are exploited to identify homogeneous market segments to which suitable

. This paper describes how the generation of hypertexts for accessing on-line news servers can be tailored to different users. News servers contain huge amounts of information, concerning different topics. The aim of our system is to present the most appropriate set of news (and advertisements) to each user, choosing the "right" level of detail for each news item. This is obtained by using knowledge representation, user modeling and flexible hypermedia techniques. 1 Introduction For several years the aims of providing customized services and reaching customer satisfaction have been the focus of communication and marketing strategies. Now the World Wide Web seems to offer very big possibilities to satisfy these needs. Thus, several efforts are being made to exploit this potential at its best. In this paper we focus on a specific service: accessing large amounts of information (news). The number of Web sites delivering news is rapidly growing (e.g., newspapers, broadcasting compa...