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| • |
Words
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– |
Author’s
words
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Indexer’s
words (metadata from a controlled
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vocabulary)
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Actions
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Human
(e.g., publisher metadata, signatures)
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System
(e.g., date, watermarks)
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| • |
Links
(citations)
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– |
Human
(citations, links)
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– |
System
(computed from events or relationships,
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recommenders)
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