- Product: Summon
How does Summon handle stop words?
Summon maintains language-specific lists of stop words, which are filtered out in the execution of searches except when they are part of formal phrase searches as described below. Stop words are chosen according to the following basic criteria.
A stop word:
- is a function word, such as a definite/indefinite article, preposition, pronoun, conjunction and auxiliary verb,
- occurs very frequently in Summon's index, and
- does not have a common secondary meaning as a content word.
Summon's current English stop words include "a", "an", "the", "and", "but", "or", "it", "of", "on", "with", "in", "is" and "are", but do not include "will" since it has a common secondary meaning as a noun.
In general, Summon ignores stop words in queries. However, in a phrase search (with search terms in double quotes), all stop words become required words, except those appearing at the end of the phrase. For example, the query 'man of the year' includes two English stop words 'of' and 'the'. If this query is issued without double quotes (i.e., man of the year), it returns results containing the words 'man' and 'year', and Summon's relevance algorithm boosts the ranking of results that contain the phrase "man of the year".
If the query is issued as a phrase search with double quotes (i.e., "man of the year"), Summon returns results containing the exact phrase "man of the year".
The language-specific lists of stop words are updated frequently in order to improve Summon's search quality and performance. For this reason, Serials Solutions does not provide lists of current stop words upon request.
- Date Created: 9-Feb-2014
- Last Edited Date: 19-July-2019
- Old Article Number: 8841