We consider a general form of information sources, consisting of a set of objects classified by terms arranged in a taxonomy. The query-based access to the information stored in sources of this kind, is plagued with uncertainty, due, among other things, to the possible linguistic mismatch between the user and the object classification. To overcome this uncertainty in all situations in which the...

Why are some words easier to learn than others? And what enables the eventual learning of the more difficult words? These questions were addressed for nouns using a paradigm in which adults were exposed to naturalistic maternal input that was manipulated to simulate access to several different information sources, both alone and in combination: observation of the extralinguistic contexts in whi...

This thesis presents a framework for integrating information from multiple heterogeneous sources. The framework consists of an HTML extension called OHTML and the W3Graph query language. OHTML adds to HTML semantic tags. The W3Graph query language is a query language for semistructured data that we designed for querying OHTML pages. We designed OHTML to enrich HTML pages with semantic informati...

Research synthesis plays a central role in the process of scientific discovery, providing a formal methodology for the systematic accumulation and evaluation of scientific evidence. There are many situations in which research synthesis is required because obtaining the required information from an individual trial is not possible or practical. This thesis proposes a general method to synthesize...

For many information domains there are numerous World Wide Web data sources. The sources vary both in their extension and their intension: They represent different real world entities with possible overlap and provide different attributes of these entities. Mediator-based information systems allow integrated access to such sources by providing a common schema against which the user can pose que...

Many applications are facing the problem of learning from an objective dataset, whereas information from other auxiliary sources may be beneficial but cannot be integrated into the objective dataset for learning. In this paper, we propose an omni-view learning approach to enable learning from multiple data collections. The theme is to organize heterogeneous data sources into a unified table wit...

The Internet provides dramatic new opportunities for gathering information from multiple, distributed, heterogeneous information sources. However, this distributed environment poses difficult technical problems for the information-seeking client, including finding the information sources relevant to an interest, formulating questions in the terms that the sources understand, interpreting the re...

Information available on the Internet is abundant but often inaccurate. Web sources have different degrees of trustworthiness based on their accuracy, freshness, origin or bias. Web users are then left with the daunting task of assessing the correctness of possibly conflicting answers to their queries. In this paper, we present techniques for corroborating information from different web sources...

The information-theoretical entropy is an effective measure of uncertainty connected with an information source. Its transfer from the classical probabilistic information theory models to the fuzzy set theoretical environment is desirable and significant attempts were realized in the existing literature. Nevertheless, there are some open topics for analysis in the suggested models of fuzzy entr...

This paper deals with the concept of the “size” or “extent” of the information in the sense of measuring the improvement of our knowledge after obtaining a message. Standard approaches are based on the probabilistic parameters of the considered information source. Here we deal with situations when the unknown probabilities are subjectively or vaguely estimated. For the considered fuzzy quantiti...