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such as "AND, OR, NOT." "AND" is normally unnecessary as most search engines infer it. "OR" will search for results with one search term or another or both. "NOT" eliminates a word or phrase from the search, getting rid of any results that include it. Multiple words can also be enclosed in quotation
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are designed to search for words anywhere in a document—the title, the body, and so on. This being the case, a keyword can be any term that exists within the document. However, priority is given to words that occur in the title, words that recur numerous times, and words that are explicitly assigned
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Author keywords are an integral part of literature. Many journals and databases provide access to index terms made by authors of the respective articles. How qualified the provider is decides the quality of both indexer-provided index terms and author-provided index terms. The quality of these two
60:, which are directly visible and can be assigned by non-experts. Index terms can consist of a word, phrase, or alphanumerical term. They are created by analyzing the document either manually with
52:, which is the function by which libraries collect, organize and disseminate documents. They are used as keywords to retrieve documents in an information system, for instance, a catalog or a
79:(a, an, the) and conjunctions (and, or, but) are not treated as keywords because it's inefficient. Almost every English-language site on the Internet has the article "
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such as "the" and "a" from its indexes for several years, but then re-introduced them, making certain types of precise search possible again.
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or more sophisticated methods of keyword extraction. Index terms can either come from a controlled vocabulary or be freely assigned.
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139:. These modifiers and methods all help to refine search terms, to better maximize the accuracy of search results.
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40:) is a term that captures the essence of the topic of a document. Index terms make up a
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83:", and so it makes no sense to search for it. The most popular search engine,
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types of index terms is of research interest, particularly in relation to
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as keywords within the coding. Index terms can be further refined using
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252:(1st MIT Press pbk. ed.). Cambridge, Massachusetts: MIT Press.
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in 1948. It is in particular used about a preferred term from a
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marks to turn the individual index terms into a specific index
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language (SKOS) provides a way to express index terms with
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The intellectual foundation of information organization
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http://www.columbia.edu/cu/lweb/help/clio/keyword.html
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292:. Columbia University Libraries. Retrieved from
184:Polythematic Structured Subject Heading System
56:. A popular form of keywords on the web are
278:https://www.youtube.com/watch?v=BNHR6IQJGZs
315:Library Resources & Technical Services
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172:Library of Congress Subject Headings
156:to other documents in the database.
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346:Information retrieval techniques
190:Subject Headings Authority File
48:. They are an integral part of
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272:Cutts, Matt. (2010, March 4).
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113:for use in the context of the
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94:The term "descriptor" was by
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311:"Birth of a Subject Heading"
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166:Canadian Subject Headings
71:Keywords are stored in a
309:Ferris, Anna M. (2018).
178:Medical Subject Headings
64:or automatically with
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121:In web search engines
50:bibliographic control
46:bibliographic records
42:controlled vocabulary
18:information retrieval
328:10.5860/lrts.62n1.16
75:. Common words like
213:Subject (documents)
203:Index (publishing)
127:web search engines
66:automatic indexing
274:How search works.
246:Svenonius, Elaine
132:Boolean operators
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321:(1): 16–27.
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44:for use in
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89:stop words
34:descriptor
22:index term
223:Tag cloud
100:thesaurus
351:Thesauri
248:(2009).
197:See also
160:Examples
154:relative
87:removed
77:articles
38:keyword
288:CLIO.
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180:(MeSH)
174:(LCSH)
137:phrase
85:Google
192:(SWD)
186:(PSH)
125:Most
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105:The
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