Introduction to Information Retrieval

Introduction to Information Retrieval
Cosine similarity between query and
document
• q i is the tf-idf weight of term i in the query.
• d i is the tf-idf weight of term i in the document.
• | | and | | are the lengths of
and
• This is the cosine similarity of and . . . . . . or,
equivalently, the cosine of the angle between and
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