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:
“It is the interest one takes in books that makes a library. And if a library have interest it is; if not, it isn’t.”
—Carolyn Wells (1862–1942)
“On the breasts of a barmaid in Sale
Were tattooed the prices of ale;
And on her behind
For the sake of the blind
Was the same information in Braille.”
—Anonymous.
“Vanity of science. Knowledge of physical science will not console me for ignorance of morality in time of affliction, but knowledge of morality will always console me for ignorance of physical science.”
—Blaise Pascal (1623–1662)