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    Summon: Did You Mean Feature


    Summon’s Did You Mean (DYM) feature offers spelling corrections for possible misspelled terms in a search query. It uses search term statistics derived from a subset of CDI’s main search index. These statistics cover all languages in CDI.

    Summon invokes the DYM algorithm on both single and multiple word queries and returns a single DYM suggestion per query.

    The DYM Algorithm

    The DYM algorithm looks for possible corrections for each term in a search query and considers various factors to find the best candidate for a correction including:

    • The edit distance between the original term and its correction candidates: this factor denotes how similar those candidates are to the original term.

    • The document frequency (df) of the original term and its correction candidates: document frequency is the number of documents containing a term, and it indicates how often the original term and the replacement candidates are in the CDI main index.

    While the user's search is processed, the DYM algorithm works in parallel looking for misspelled words to ensure that the overall search response time is not affected.

    Internationalized DYM Feature

    The DYM feature fully supports English language searches as well as other languages. In some cases, when searching in languages other than English, the DYM service may offer suggestions in a language other than the searched language or may fail to offer corrections for misspellings in the searched language. This happens because the term statistics are skewed toward English due to the high percentage of English content in CDI. For example, a French user may issue a search in French and get a suggestion for an English word. Or a Japanese user may issue a search in Japanese and get a suggestion for a Chinese word.

    In order to provide a better user experience, Summon offers Internationalized DYM suggestions for some languages and is based on the user’s UI language, and prioritizes suggestions for words in the user’s UI language.

    The following languages are currently supported for the Internationalized DYM feature:

    • Simplified Chinese

    • Traditional Chinese

    • Japanese

    • French

    • German

    • Swedish

    • Norwegian

    • Italian

    For all other languages, Summon uses the default DYM algorithm. Support for additional languages will be added in the future.

    The Enhanced DYM Feature

    Starting in December 2021, the Enhanced DYM feature offers automatic spelling corrections in addition to suggestions. Whether it makes a correction or a suggestion depends on the likelihood of misspelling.

    If a search query contains one or more words that are very likely misspelled, Summon automatically replaces the words in the query, and shows the following information:

    • Showing results for: <corrected search>

    • Search instead for: <original search>

    If the algorithm finds a correction candidate with a low probability of misspelling, Summon displays a DYM suggestion instead of the automatic correction above.

    • Did you mean: <corrected search>


    • Unlike the original DYM feature, the enhanced version may increase search response times because it needs to look for possible corrections before issuing the main search.

    • At this time, the Enhanced DYM feature supports only English language searches and works only from the English UI.

    Example 1 - Automatic Correction

    Searching for biolgy automatically corrects the query and shows the results for biology:

    • Showing results for: biology

    • Search instead for: biolgy

    The second line above contains a clickable link that allows users to perform the original search if the automatic correction is not needed.

    Example 2 - Suggestion

    Searching for jhonathan does not automatically show results for jonathan, but it shows the following suggestion:

    • Did you mean: jonathan

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