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Abstract

Various kinds of knowledge organisation, such as thesauri, are routinely used to label or tag multimedia content such as images and music and to support information retrieval, i.e. user search for such content. In this paper, we outline why this is the case, in particular focusing on the semantic gap between content and concept based multimedia retrieval. We survey some indexing vocabularies used for multimedia retrieval, and argue that techniques such as thesauri will be needed for the foreseeable future in order to support users in their need for multimedia content. In particular, we argue that artificial intelligence techniques are not mature enough to solve the problem of indexing multimedia conceptually and will not be able to replace human indexers for the foreseeable future.

Content

Beitrag in einem Special issue: The Great Debate: "This House Believes that the Traditional Thesaurus has no Place in Modern Information Retrieval." [19 February 2015, 14:00-17:30 preceded by ISKO UK AGM and followed by networking, wine and nibbles; vgl.: http://www.iskouk.org/content/great-debate].

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Abstract

The introduction (1.0) of this article considers the status of the thesaurus within LIS and asks about the future prospect for thesauri. The main following points are: (2.0) Any knowledge organization system (KOS) is today threatened by Google-like systems, and it is therefore important to consider if there still is a need for knowledge organization (KO) in the traditional sense. (3.0) A thesaurus is a somewhat reduced form of KOS compared to, for example, an ontology, and its "bundling" and restricted number of semantic relations has never been justified theoretically or empirically. Which semantic relations are most fruitful for a given task is thus an open question, and different domains may need different kinds of KOS including different sets of relations between terms. (4.0) A KOS is a controlled vocabulary (CV) and should not be considered a "perfect language" (Eco 1995) that is simply able to remove the ambiguity of natural language; rather much ambiguity in language represents a battle between many "voices" (Bakhtin 1981) or "paradigms" (Kuhn 1962). In this perspective, a specific KOS, e.g. a specific thesaurus, is just one "voice" among many voices, and that voice has to demonstrate its authority and utility. It is concluded (5.0) that the traditional thesaurus does not have a place in modern information retrieval, but that more flexible semantic tools based on proper studies of domains will always be important.

Content

Beitrag in einem Special issue: The Great Debate: "This House Believes that the Traditional Thesaurus has no Place in Modern Information Retrieval." [19 February 2015, 14:00-17:30 preceded by ISKO UK AGM and followed by networking, wine and nibbles; vgl.: http://www.iskouk.org/content/great-debate].

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Abstract

Thesauri have triumphed in many domains that require precise and exhaustive information because of their representational power, their capability to integrate the concept-based and alphabetical approaches to organizing information, and their standardization and, more recently, formalization. Nevertheless, there is room to improve their relevance in the digital age by embracing the open linked data initiatives and by taking advantage of their structural and functional proximity to some of the big collaborative knowledge repositories in the Internet, notably the Wikipedia environment. With a focus on its implications for enhanced interoperability, this structural proximity is analysed, and the benefits of such collaboration for the different potential stakeholders are considered. It is proposed that better devices for ensuring semantic browsing are provided when necessary, and that an open hub for thesauri interconnection is developed, perhaps using existing big open Internet semantic facilities, such as Wikipedia.

Content

Beitrag in einem Special issue: The Great Debate: "This House Believes that the Traditional Thesaurus has no Place in Modern Information Retrieval." [19 February 2015, 14:00-17:30 preceded by ISKO UK AGM and followed by networking, wine and nibbles; vgl.: http://www.iskouk.org/content/great-debate].

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Content

Einführung in ein Special issue: The Great Debate: "This House Believes that the Traditional Thesaurus has no Place in Modern Information Retrieval." [19 February 2015, 14:00-17:30 preceded by ISKO UK AGM and followed by networking, wine and nibbles; vgl.: http://www.iskouk.org/content/great-debate].

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Content

Resumee zu einem Special issue: The Great Debate: "This House Believes that the Traditional Thesaurus has no Place in Modern Information Retrieval." [19 February 2015, 14:00-17:30 preceded by ISKO UK AGM and followed by networking, wine and nibbles; vgl.: http://www.iskouk.org/content/great-debate].

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Abstract

The paper analysed here is a kind of position paper. In order to get a better under-standing of the reported work I used the retrieval interface of the thesaurus, the so-called NCI DTS Browser accessible via the Web3, and I perused the cited OWL file4 with numerous "Find" and "Find next" string searches. In addition the file was im-ported into Protégé 2000, Release 2.0, with OWL Plugin 1.0 and Racer Plugin 1.7.14. At the end of the paper's introduction the authors say: "In the following sections, this paper will describe the terminology development process at NCI, and the issues associated with converting a description logic based nomenclature to a semantically rich OWL ontology." While I will not deal with the first part, i.e. the terminology development process at NCI, I do not see the thesaurus as a description logic based nomenclature, or its cur-rent state and conversion already result in a "rich" OWL ontology. What does "rich" mean here? According to my view there is a great quantity of concepts and links but a very poor description logic structure which enables inferences. And what does the fol-lowing really mean, which is said a few lines previously: "Although editors have defined a number of named ontologic relations to support the description-logic based structure of the Thesaurus, additional relation-ships are considered for inclusion as required to support dependent applications."
According to my findings several relations available in the thesaurus query interface as "roles", are not used, i.e. there are not yet any assertions with them. And those which are used do not contribute to complete concept definitions of concepts which represent thesaurus main entries. In other words: The authors claim to already have a "description logic based nomenclature", where there is not yet one which deserves that title by being much more than a thesaurus with strict subsumption and additional inheritable semantic links. In the last section of the paper the authors say: "The most time consuming process in this conversion was making a careful analysis of the Thesaurus to understand the best way to translate it into OWL." "For other conversions, these same types of distinctions and decisions must be made. The expressive power of a proprietary encoding can vary widely from that in OWL or RDF. Understanding the original semantics and engineering a solution that most closely duplicates it is critical for creating a useful and accu-rate ontology." My question is: What decisions were made and are they exemplary, can they be rec-ommended as "the best way"? I raise strong doubts with respect to that, and I miss more profound discussions of the issues at stake. The following notes are dedicated to a critical description and assessment of the results of that conversion activity. They are written in a tutorial style more or less addressing students, but myself being a learner especially in the field of medical knowledge representation I do not speak "ex cathedra".

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Content

Beitrag in einem Special issue: The Great Debate: "This House Believes that the Traditional Thesaurus has no Place in Modern Information Retrieval." [19 February 2015, 14:00-17:30 preceded by ISKO UK AGM and followed by networking, wine and nibbles; vgl.: http://www.iskouk.org/content/great-debate].

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Content

Beitrag in einem Special issue: The Great Debate: "This House Believes that the Traditional Thesaurus has no Place in Modern Information Retrieval." [19 February 2015, 14:00-17:30 preceded by ISKO UK AGM and followed by networking, wine and nibbles; vgl.: http://www.iskouk.org/content/great-debate].

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Abstract

The present study investigates the ability of a bibliometric based semi-automatic method to select candidate thesaurus terms from citation contexts. The method consists of document co-citation analysis, citation context analysis, and noun phrase parsing. The investigation is carried out within the specialty area of periodontology. The results clearly demonstrate that the method is able to select important candidate thesaurus terms within the chosen specialty area.

Date

8. 3.2007 19:55:22

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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

Once upon a time, the thesaurus was venerated. It marked a breakthrough in the retrieval of very specific needles of information hidden in large haystacks. Some of the veneration rubbed off on to the trained information professionals, who alone mastered the occult art of using it to concoct effective search strategies. All this was in the time before we had a computer on every desk, when a collection of 10,000 articles was considered large, and long before the Google era. But now, who has the patience to consult a complicated thesaurus? Only a dedicated few. Has the thesaurus passed its sell-by date? And even its use-by date? These questions, and more, were tossed around at the Great Debate by a community of enthusiasts. While some limitations of the old-fashioned (?) thesaurus were noted, it still received a happy vote of confidence at the end. - Judi Vernau (2015) First speaker for the proposition - Vanda Broughton (2015) First speaker for the opposition - Helen Lippell (2015) Second speaker for the proposition - Leonard Will (2015) Second speaker for the opposition - Cross-examination of expert witnesses - Martin White (2015) Questions and discussion from the floor

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Content

Beitrag in einem Special issue: The Great Debate: "This House Believes that the Traditional Thesaurus has no Place in Modern Information Retrieval." [19 February 2015, 14:00-17:30 preceded by ISKO UK AGM and followed by networking, wine and nibbles; vgl.: http://www.iskouk.org/content/great-debate].

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Content

Beitrag in einem Special issue: The Great Debate: "This House Believes that the Traditional Thesaurus has no Place in Modern Information Retrieval." [19 February 2015, 14:00-17:30 preceded by ISKO UK AGM and followed by networking, wine and nibbles; vgl.: http://www.iskouk.org/content/great-debate].

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Abstract

The benefits of a well constructed thesaurus to an information retrieval system have long been recognised by both researchers and practitioners in the field. Examines both early and current approaches to automatic thesaurus construction and describes an approach to the automatic generation of global thesauri based on the term discrimination value model of Salton Yang, and Yu and on an appropriate clustering algorithm. This method has been implemented and applied to 2 document collections. Preliminary results indicate that this method, which produces improvements in retrieval performance in excess of 10 and 15% in the test collections, is viable and worthy of continued investigation.

Date

22. 4.1996 3:39:53

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Abstract

After a period of experiment and evolution in the 1950s and 1960s, a fairly standard format for thesauri was established with the publication of the influential Thesaurus of Engineering and Scientific Terms (TEST) in 1967. This and other early thesauri relied primarily an the presentation of terms in alphabetical order. The value of a classified presentation was subsequently realised, and in particular the technique of facet analysis has profoundly influenced thesaurus evolution. Thesaurofacet and the Art & Architecture Thesaurus have acted as models for two distinct breeds of thesaurus using faceted displays of terms. As of the 1990s, the expansion of end-user access to vast networked resources is imposing further requirements an the style and structure of controlled vocabularies. The international standards for thesauri, first conceived in a print-based era, are badly in need of updating. Work is in hand in the UK and the USA to revise and develop standards in support of electronic thesauri.

Date

22. 9.2007 15:46:13

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Abstract

The need for Persian thesauri became apparent during the late 1960s with the advent of documentation centres in Iran. The first Persian controlled vocabulary was published by IRANDOC in 1977. Other centres worked on translations of existing thesauri, but it was soon realised that these efforts did not meet the needs of the centres. After the Islamic revolution in 1979, the foundation of new centres intensified the need for Persian thesauri, especially in the fields of history and government documents. Also, during the Iran-Iraq war, Iranian research centres produced reports in scientific and technical fields, both to support military requirements and to meet society's needs. In order to provide a comprehensive thesaurus, the Council of Scientific Research of Iran approved a project for the compilation of such a work. Nowadays, 12 Persian thesauri are available and others are being prepared, based on the literary corpus and conformity with characteristics of Iranian culture.

Source

Indexer. 25(2006) no.1, S.19-22

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Abstract

Presents a framework for knowledge discovery and concept exploration. In order to enhance the concept exploration capability of knowledge based systems and to alleviate the limitation of the manual browsing approach, develops 2 spreading activation based algorithms for concept exploration in large, heterogeneous networks of concepts (eg multiple thesauri). One algorithm, which is based on the symbolic AI paradigma, performs a conventional branch-and-bound search on a semantic net representation to identify other highly relevant concepts (a serial, optimal search process). The 2nd algorithm, which is absed on the neural network approach, executes the Hopfield net parallel relaxation and convergence process to identify 'convergent' concepts for some initial queries (a parallel, heuristic search process). Tests these 2 algorithms on a large text-based knowledge network of about 13.000 nodes (terms) and 80.000 directed links in the area of computing technologies