Search (17 results, page 1 of 1)

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Abstract

Purpose The purpose of this paper is to identify the concepts, component parts and relationships between vocabularies, linked data and knowledge graphs (KGs) from the perspectives of data and knowledge transitions. Design/methodology/approach This paper uses conceptual analysis methods. This study focuses on distinguishing concepts and analyzing composition and intercorrelations to explore data and knowledge transitions. Findings Vocabularies are the cornerstone for accurately building understanding of the meaning of data. Vocabularies provide for a data-sharing model and play an important role in supporting the semantic expression of linked data and defining the schema layer; they are also used for entity recognition, alignment and linkage for KGs. KGs, which consist of a schema layer and a data layer, are presented as cubes that organically combine vocabularies, linked data and big data. Originality/value This paper first describes the composition of vocabularies, linked data and KGs. More importantly, this paper innovatively analyzes and summarizes the interrelatedness of these factors, which comes from frequent interactions between data and knowledge. The three factors empower each other and can ultimately empower the Semantic Web.

Date

22. 1.2021 14:24:32

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Abstract

Calvin Mooers' work toward the resolution of the problem of ambiguity in indexing went unrecognized for years. At the time he introduced the "descriptor" - a term with a very distinct meaning-indexers were, for the most part, taking index terms directly from the document, without either rationalizing them with context or normalizing them with some kind of classification. It is ironic that Mooers' term came to be attached to the popular but unsophisticated indexing methods which he was trying to root out. Simply expressed, what Mooers did was to take the dictionary definitions of terms and redefine them so clearly that they could not be used in any context except that provided by the new definition. He did, at great pains, construct such meanings for over four hundred words; disambiguation and specificity were sought after and found for these words. He proposed that all indexers adopt this method so that when the index supplied a term, it also supplied the exact meaning for that term as used in the indexed document. The same term used differently in another document would be defined differently and possibly renamed to avoid ambiguity. The disambiguation was achieved by using unabridged dictionaries and other sources of defining terminology. In practice, this tends to produce circularity in definition, that is, word A refers to word B which refers to word C which refers to word A. It was necessary, therefore, to break this chain by creating a new, definitive meaning for each word. Eventually, means such as those used by Austin (q.v.) for PRECIS achieved the same purpose, but by much more complex means than just creating a unique definition of each term. Mooers, however, was probably the first to realize how confusing undefined terminology could be. Early automatic indexers dealt with distinct disciplines and, as long as they did not stray beyond disciplinary boundaries, a quick and dirty keyword approach was satisfactory. The trouble came when attempts were made to make a combined index for two or more distinct disciplines. A number of processes have since been developed, mostly involving tagging of some kind or use of strings. Mooers' solution has rarely been considered seriously and probably would be extremely difficult to apply now because of so much interdisciplinarity. But for a specific, weIl defined field, it is still weIl worth considering. Mooers received training in mathematics and physics from the University of Minnesota and the Massachusetts Institute of Technology. He was the founder of Zator Company, which developed and marketed a coded card information retrieval system, and of Rockford Research, Inc., which engages in research in information science. He is the inventor of the TRAC computer language.

Footnote

Original in: Information retrieval today: papers presented at an Institute conducted by the Library School and the Center for Continuation Study, University of Minnesota, Sept. 19-22, 1962. Ed. by Wesley Simonton. Minneapolis, Minn.: The Center, 1963. S.21-36.

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Abstract

Der Computer kann mit sprachlichen Zeichen sicher und schnell umgehen. Dies zeigen Programme zur Textverarbeitung. Versuche allerdings, ihn auch mit Bedeutungen operieren zu lassen, sind gescheitert. Wird der Rechner das größte Problem der Sprachverarbeitung - die Mehrdeutigkeit natürlicher Sprachen - jemals bewältigen?

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Abstract

This chapter presents a broad survey of the cause-effect relation, with particular emphasis an how the relation is expressed in text. Philosophers have been grappling with the concept of causation for centuries. Researchers in social psychology have found that the human mind has a very complex mechanism for identifying and attributing the cause for an event. Inferring cause-effect relations between events and statements has also been found to be an important part of reading and text comprehension, especially for narrative text. Though many of the cause-effect relations in text are implied and have to be inferred by the reader, there is also a wide variety of linguistic expressions for explicitly indicating cause and effect. In addition, it has been found that certain words have "causal valence"-they bias the reader to attribute cause in certain ways. Cause-effect relations can also be divided into several different types.

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Date

8.10.2000 11:52:22

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Abstract

Purpose - The purpose of this paper is to summarize the varied structural characteristics which may be present in retrieval languages. Design/methodology/approach - The languages serve varied purposes in information systems, and a number of these are identified. The relations between structure and function are discussed and suggestions made as to the most suitable structures needed for various purposes. Findings - A quantitative approach has been developed: a simple measure is the number of separate terms in a retrieval language, but this has to be related to the scope of its subject field. Some ratio of terms to items in the field seems a more suitable measure of the average specificity of the terms. Other aspects can be quantified - for example, the average number of links in hierarchical chains, or the average number of cross-references in a thesaurus. Originality/value - All the approaches to the analysis of retrieval language reported in this paper are of continuing value. Some practical studies of computer information systems undertaken by Aslib Research Department have suggested a further approach.

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Abstract

The current standards for monolingual and multilingual thesauri are long overdue for an update. This applies to the international standards ISO 2788 and ISO 5964, as well as the corresponding national standards in several countries and the American standard ANSI/NISO Z39.19. Work is now under way in the UK and in the USA to revise and extend the standards, with particular emphasis on interoperability needs in our world of vast electronic networks. Work in the UK is starting with the British Standards, in the hope of leading on to one international standard to serve all. Some of the issues still under discussion include the treatment of facet analysis, coverage of additional types of controlled vocabulary such as classification schemes, taxonomies and ontologies, and mapping from one vocabulary to another. 1. Are thesaurus standards still needed? Since the 1960s, even before the renowned Cranfield experiments (Cleverdon et al., 1966; Cleverdon, 1967) arguments have raged over the usefulness or otherwise of controlled vocabularies. The case has never been proved definitively one way or the other. At the same time, a recognition has become widespread that no one search method can answer all retrieval requirements. In today's environment of very large networks of resources, the skilled information professional uses a range of techniques. Among these, controlled vocabularies are valued alongside others. The first international standard for monolingual thesauri was issued in 1974. In those days, the main application was for postcoordinate indexing and retrieval from document collections or bibliographic databases. For many information professionals the only practicable alternative to a thesaurus was a classification scheme. And so the thesaurus developed a strong following. After computer systems with full text search capability became widely available, however, the arguments against controlled vocabularies gained more followers. The cost of building and maintaining a thesaurus or a classification scheme was a strong disincentive. Today's databases are typically immense compared with those three decades ago. Full text searching is taken for granted, not just in discrete databases but across all the resources in an intranet or even the Internet. But intranets have brought particular frustration as users discover that despite all the computer power, they cannot find items which they know to be present an the network. So the trend against controlled vocabularies is now being reversed, as many information professionals are turning to them for help. Standards to guide them are still in demand.

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Date

31. 7.2006 14:22:21

Source

Cataloging and classification quarterly. 22(1996) no.1, S.77-93

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Pages

S.11-22

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Abstract

The use of diagrams to express relationships in classification is not new. Many classificationists have used this approach, but usually in a minor display to make a point or for part of a difficult relational situation. Ranganathan, for example, used diagrams for some of his more elusive concepts. The thesaurus in particular and subject headings in general, with direct and indirect crossreferences or equivalents, need many more diagrams than normally are included to make relationships and even semantics clear. A picture very often is worth a thousand words. Rolling has used directed graphs (arrowgraphs) to join terms as a practical method for rendering relationships between indexing terms lucid. He has succeeded very weIl in this endeavor. Four diagrams in this selection are all that one needs to explain how to employ the system; from initial listing to completed arrowgraph. The samples of his work include illustration of off-page connectors between arrowgraphs. The great advantage to using diagrams like this is that they present relations between individual terms in a format that is easy to comprehend. But of even greater value is the fact that one can use his arrowgraphs as schematics for making three-dimensional wire-and-ball models, in which the relationships may be seen even more clearly. In fact, errors or gaps in relations are much easier to find with this methodology. One also can get across the notion of the threedimensionality of classification systems with such models. Pettee's "hand reaching up and over" (q.v.) is not a figment of the imagination. While the actual hand is a wire or stick, the concept visualized is helpful in illuminating the three-dimensional figure that is latent in all systems that have cross-references or "broader," "narrower," or, especially, "related" terms. Classification schedules, being hemmed in by the dimensions of the printed page, also benefit from such physical illustrations. Rolling, an engineer by conviction, was the developer of information systems for the Cobalt Institute, the European Atomic Energy Community, and European Coal and Steel Community. He also developed and promoted computer-aided translation at the Commission of the European Communities in Luxembourg. One of his objectives has always been to increase the efficiency of mono- and multilingual thesauri for use in multinational information systems.

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Date

1. 8.1996 22:01:00

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Date

22. 9.2007 15:45:57

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Source

Wissensspeicher in digitalen Räumen: Nachhaltigkeit - Verfügbarkeit - semantische Interoperabilität. Proceedings der 11. Tagung der Deutschen Sektion der Internationalen Gesellschaft für Wissensorganisation, Konstanz, 20. bis 22. Februar 2008. Hrsg.: J. Sieglerschmidt u. H.P.Ohly

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Abstract

This chapter from The Sayers Memorial Volume summarizes Farradane's earlier work in which he developed his major themes by drawing in part upon research in psychology, and particularly those discoveries called "cognitive" which now form part of cognitive science. Farradane, a chemist by training who later became an information scientist and Director of the Center for Information Science, City University, London, from 1958 to 1973, defines the various types of methods used to achieve classification systems-philosophic, scientific, and synthetic. Early an he distinguishes the view that classification is "some part of external 'reality' waiting to be discovered" from that view which considers it "an intellectual operation upon mental entities and concepts." Classification, therefore, is to be treated as a mental construct and not as something "out there" to be discovered as, say, in astronomy or botany. His approach could be termed, somewhat facetiously, as an "in there" one, meaning found by utilizing the human brain as the key tool. This is not to say that discoveries in astronomy or botany do not require the use of the brain as a key tool. It is merely that the "material" worked upon by this tool is presented to it for observation by "that inward eye," by memory and by inference rather than by planned physical observation, memory, and inference. This distinction could be refined or clarified by considering the initial "observation" as a specific kind of mental set required in each case. Farradane then proceeds to demolish the notion of main classes as "fictitious," partly because the various category-defining methodologies used in library classification are "randomly mixed." The implication, probably correct, is that this results in mixed metaphorical concepts. It is an interesting contrast to the approach of Julia Pettee (q.v.), who began with indexing terms and, in studying relationships between terms, discovered hidden hierarchies both between the terms themselves and between the cross-references leading from one term or set of terms to another. One is tempted to ask two questions: "Is hierarchy innate but misinterpreted?" and "ls it possible to have meaningful terms which have only categorical relationships (that have no see also or equivalent relationships to other, out-of-category terms)?" Partly as a result of the rejection of existing general library classification systems, the Classification Research Group-of which Farradane was a charter member decided to adopt the principles of Ranganathan's faceted classification system, while rejecting his limit an the number of fundamental categories. The advantage of the faceted method is that it is created by inductive, rather than deductive, methods. It can be altered more readily to keep up with changes in and additions to the knowledge base in a subject without having to re-do the major schedules. In 1961, when Farradane's paper appeared, the computer was beginning to be viewed as a tool for solving all information retrieval problems. He tartly remarks:

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Date

1. 8.1996 22:01:00

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Abstract

This chapter examines the nature of semantic relations and their main applications in information science. The nature and types of semantic relations are discussed from the perspectives of linguistics and psychology. An overview of the semantic relations used in knowledge structures such as thesauri and ontologies is provided, as well as the main techniques used in the automatic extraction of semantic relations from text. The chapter then reviews the use of semantic relations in information extraction, information retrieval, question-answering, and automatic text summarization applications. Concepts and relations are the foundation of knowledge and thought. When we look at the world, we perceive not a mass of colors but objects to which we automatically assign category labels. Our perceptual system automatically segments the world into concepts and categories. Concepts are the building blocks of knowledge; relations act as the cement that links concepts into knowledge structures. We spend much of our lives identifying regular associations and relations between objects, events, and processes so that the world has an understandable structure and predictability. Our lives and work depend on the accuracy and richness of this knowledge structure and its web of relations. Relations are needed for reasoning and inferencing. Chaffin and Herrmann (1988b, p. 290) noted that "relations between ideas have long been viewed as basic to thought, language, comprehension, and memory." Aristotle's Metaphysics (Aristotle, 1961; McKeon, expounded on several types of relations. The majority of the 30 entries in a section of the Metaphysics known today as the Philosophical Lexicon referred to relations and attributes, including cause, part-whole, same and opposite, quality (i.e., attribute) and kind-of, and defined different types of each relation. Hume (1955) pointed out that there is a connection between successive ideas in our minds, even in our dreams, and that the introduction of an idea in our mind automatically recalls an associated idea. He argued that all the objects of human reasoning are divided into relations of ideas and matters of fact and that factual reasoning is founded on the cause-effect relation. His Treatise of Human Nature identified seven kinds of relations: resemblance, identity, relations of time and place, proportion in quantity or number, degrees in quality, contrariety, and causation. Mill (1974, pp. 989-1004) discoursed on several types of relations, claiming that all things are either feelings, substances, or attributes, and that attributes can be a quality (which belongs to one object) or a relation to other objects.