This paper surveys the use of Spreading Activation techniques on Semantic Networks in Associative Information Retrieval. The major Spreading Activation models are presented and their applications to IR is surveyed. A number of works in this area are critically analyzed in order to study the relevance of Spreading Activation for associative IR. Key words: spreading activation, information storage and retrieval, semantic networks, associative information retrieval, information processing, knowledge representation.

The recent advances in Formal Concept Analysis (FCA) together with the major changes faced by modern Information Retrieval (IR) provide new unprecedented challenges and opportunities for FCA-based IR applications. The main advantage of FCA for IR is the possibility of creating a conceptual representation of a given document collection in the form of a document lattice, which may be used both to improve the retrieval of specific items and to drive the mining of the collection’s contents. In this paper, we will examine the best features of FCA for solving IR tasks that could not be easily addressed by conventional systems, as well as the most critical aspects for building FCA-based IR applications. These observations have led to the development of CREDO, a system that allows the user to query Web documents and see retrieval results organized in a browsable concept lattice. This is the second major focus of the paper. We will show that CREDO is especially useful for quickly locating the documents corresponding to the meaning of interest among those retrieved in response to an ambiguous query, or for mining the contents of the documents that reference a given entity. An on-line version of the system is available for testing at

The rst part of the paper brie y introduces what automatic authoring of a hypertext for information retrieval means. The most di cult part of the automatic construction of a hypertext is the creation of links connecting documents or document fragments that are semantically related. Because of this, to many researchers it seemed natural to use IR techniques for this purpose, since IR has always dealt with the construction of relationships between objects mutually relevant. The second part of the paper presents a survey of some of attempts toward the automatic construction of hypertexts for information retrieval. This part will identify and compare scope, advantages and limitations of di erent approaches. The aim of this survey is to point out the main and most successful current lines of research.

In this paper we present a comprehensive approach to automatic organization and hybrid navigation of text databases. An organizing stage first builds a particular lattice representation of the data, through text indexing followed by lattice clustering of the indexed texts. The lattice representation, then, supports the navigation stage of the system, a visual retrieval interface that combines three main retrieval strategies: browsing, querying, and bounding. Browsing and querying are used to search the retrieval space, bounding is used to restrict it based on the information that users have, or get during their interaction with the system. We show that such a hybrid paradigm permits high flexibility in trading off information exploration and retrieval and, in addition, has good retrieval performance. We compared information retrieval using lattice-based hybrid navigation with conventional Boolean querying. The results of an experiment conducted on two medium-sized bibliographic databases showed that the performance of lattice retrieval was comparable to or better than Boolean retrieval

This paper presents the results of two separate studies into electronic book production. The Visual Book (Landoni, 1997) which explored the importance of the visual component of the book metaphor in the production of “good ” electronic books, and the Hyper-TextBook (Crestani and Melucci, 1998a) which instead concentrated on the importance of hypertext models for the automatic production of functional electronic books. Both studies started from similar considerations on what kinds of paper books are more suitable for being translated into electronic form and both identified as target publications which are meant to be used as references more than sequentially read by users. The result of these two research strands is critically presented in this paper, with the aim of integrating them in a more general research work aimed at providing a complete methodology on how to produce electronic books in a cheap and fast way, so that they are visually appealing and at the same provide the user with a set of desirable searching and browsing functionalities. 1