Introduces the concept of relevance as viewed and applied in the context of IR (information retrieval) evaluation by presenting an overview of the multidimensionality and dynamic nature of the concept. Topics include classes and types of relevance; relevance criteria; degrees of relevance; levels of relevance; situational relevance; and…

Discussion of probabilistic information retrieval (IR) systems challenges the probability ranking principle in IR from the perspective of (1) signal detection-decision theory and (2) utility theory. Calibration, certainty, and independent assessment are discussed in terms of the relevance of documents, and standard retrieval policies are analyzed.…

Describes results of a study that investigated the effect of variations in indexing exhaustivity on retrieval performance in a vector space retrieval system. The test collection of documents in the National Library of Medicine's Medline file indexed under cystic fibrosis is described, and use of the SMART information retrieval system is discussed.…

Discussion of information-retrieval effectiveness focuses on the use of multiple query or document representations, or multiple retrieval techniques, and combining the retrieval results (also known as data fusion). Experimental results with the SMART System (developed at Harvard and Cornell Universities for over 38 years) indicate combining…

Describes SENTINEL, a prototype information-retrieval system that is a fusion of multiple information-retrieval technologies, integrating n-grams, a vector space model, and a neural network training rule. Discusses three-dimensional visualization capability, precision and recall, mathematical representation of a document, query building, and…

Presents an approach to a Genetic Information Retrieval Agent Filter (GIRAF) that filters and ranks documents retrieved from the Internet according to users' preferences by using a Genetic Algorithm and fuzzy set theory to handle the imprecision of users' preferences and users' evaluation of the retrieved documents. (Author/LRW)

Reports the results of a study of users' perceptions of relevance of documents that focused on evaluating the effectiveness of a telephone-based information retrieval service. Studies how users' perceptions varied depending on the form in which retrieved documents were presented, from full text to a machine-spoken summary. (Contains 27…

Presents a unified mathematical definition for the classical models of information retrieval and identifies a mathematical structure behind relevance feedback. Highlights include vector information retrieval; probabilistic information retrieval; and similarity information retrieval. (Contains 118 references.) (Author/LRW)

Reports on the progress of the natural language information retrieval project, a joint effort led by GE (General Electric) Research, and its evaluation at the sixth TREC (Text Retrieval Conference). Discusses stream-based information retrieval, which uses alternative methods of document indexing; advanced linguistic streams; weighting; and query…

Student evaluations to measure the teaching effectiveness of instructor's are very frequently applied in higher education for many years. This study investigates the factors associated with the assessment of instructors teaching performance using two different data mining techniques; stepwise regression and decision trees. The data collected…

As individuals become more and more comfortable mediating all kinds of situations online and through various technologies, their virtual selves increasingly overlap their "real" lives. Posting a "happy birthday!" message on Facebook is as automatic as dropping a card in the mail. E-mailing relevant links to co-workers happens as naturally as…

With the increase in available educational data, it is expected that Learning Analytics will become a powerful means to inform and support learners, teachers and their institutions in better understanding and predicting personal learning needs and performance. However, the processes and requirements behind the beneficial application of Learning…

Reports on an evaluation of the construction of selective dissemination of information profiles for the International Nuclear Information System (INIS) in South Africa. (PF)

Methods of testing systems in practice and in theory are critically reviewed. Some new theoretical considerations are advanced. (Author)

Explores the possibility of combining the two principles of ranking according to degree of relevance, and ranking according to probability of relevance, for information retrieval systems, but concludes that, while neither is adequate alone, no single, all-embracing ranking principle can be constructed to replace the two. (Author/VT)