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    Search Expansion With Controlled Vocabulary

    If you are working with Primo VE and not Primo, see Search Expansion with Controlled Vocabulary for Primo VE.
    The Controlled Vocabulary service is an external Primo service (similar to AutoComplete) that expands user searches with words and phrases that constitute variations of the search term with the same meaning, thereby increasing the accuracy of the users' searches. This service is similar to the expansion with synonyms feature but is more robust. The expansions are visible on the screen and add, for example, variations of the search term with the same meaning (example ADHD and attention deficit disorder, or name variations such as assata shakur and asata shakur). Users are provided with an option to revert to using only their original search term. All customers will see this expansion above the results in searches that include the Primo Central search scope. For all hosted customers (not on-premises), these expansions are applied to local search scopes, too. Over time, the controlled vocabulary repository will be extended so that users will see more expansions in their search results.
    For example, if the user enters heart attack in the query, Primo also returns results that include myocardial infarction. If the user is interested only in results that include heart attack, the user can click the link to the right of the recommendation.
    Example of the Controlled Vocabulary Service in Primo Central

    If the query contains more than one term that can be expanded, the system will expand only the longest term. For example, if a user searches for informatics heart attack, the system will expand heart attack (12 characters) because it contains more characters than informatics (11 characters).

    • If the user's query contains Boolean operators (for example, heart attack AND surgery), the system will not provide an expansion for the term (for example, myocardial infarction will not be included ).

    • Regardless of the phrase's context, expansions will be added.

    • Expansions are not usually bi-directional (for example, the term myocardial infarction is not expanded to the term heart attack).

    This service is applicable to both on-premises and hosted environments, but it is available only in the new Primo user interface. With a later release, it will be available in the classic user interface as well.

    Back Office Configuration

    The suggestion index is not customizable and contains LC, MeSH, and Wikipedia subject lists to provide the expanded search term suggestions.
    Out of the box, this service is enabled. If you would like to disable it, clear the Use Controlled Vocabulary Search Expansion check box in the Search Engine Configuration Wizard (Primo Home > Advanced Configuration > Search Engine Configurations).
    Enable/Disable Controlled Vocabulary Expansions
    The following codes in the Results Tile code table allow you to modify or translate the labels for this service:
    • default.nui.results.controlVocabulary.includingIncluding {{equivalentTerm}}.
    • default.nui.results.controlVocabulary.searchOnlyJust search {{query}}
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