How Voyager Calculates Relevancy of Search Results

Owned by Cooper Labenske
Apr 06, 2022
1 min read

When Voyager executes a query against an index, it lists more-relevant items at the top of the index and less-relevant items at the bottom.

Calculating Relevance Scores

Voyager  uses the following field-related factors in determining the relative relevance of index items.  

  • tf (Term Frequency) 
    This is the frequency with which a query term appears in a document. The more times a term appears, the higher the score. 

  • idf (Inverse Document Frequency) If a query term has very low frequency across all items in the index, it contributes more to the relevancy score.  

  • coord (Coordination Factor) 
    Documents that contain more query terms have higher scores.

  • fieldNorm (Field length) Fields with more words in them have lower scores than fields with fewer words. 

NOTE: Scores are always normalized so that they fall between 0 and 1.0. That means that scores are a function of a specific query against a specific index, and cannot be compared across different queries or even with the same query using a different index. 

 See Also