Library and Information Science
This field has considered when documents (or document representations) retrieved from databases are relevant or non-relevant. Given a conception of relevance, two measures have been applied: Precision and recall:
Recall = a : (a + c) X 100%, where a = number of retrieved, relevant documents, c = number of non-retrieved, relevant documents (sometimes termed "silence"). Recall is thus an expression of how exhaustive a search for documents is.
Precision = a : (a + b) X 100%, where a = number of retrieved, relevant documents, b = number of retrieved, non-relevant documents (often termed "noise").
Precision is thus an a measure of the amount of noise in document-retrieval.
Relevance itself has in the literature often been based on what is termed "the system's view" and "the user's view". Hjørland (2010) criticize these two views and defends a "subject knowledge view of relevance".
Read more about this topic: Relevance
Famous quotes containing the words library, information and/or science:
“Knowing I loved my books, he furnished me
From mine own library with volumes that
I prize above my dukedom.”
—William Shakespeare (1564–1616)
“In the information age, you don’t teach philosophy as they did after feudalism. You perform it. If Aristotle were alive today he’d have a talk show.”
—Timothy Leary (b. 1920)
“May we not assure ourselves that whatever woman’s thought and study shall embrace will thereby receive a new inspiration, that she will save science from materialism, and art from a gross realism; that the “eternal womanly shall lead upward and onward”?”
—Louisa Parsons Hopkins, U.S. scientist and author. As quoted in The Fair Women, ch. 16, by Jeanne Madeline Weimann (1981)