Text Similarity

Overview

Text similarity measures how close two texts are in meaning or surface form. Lexical methods (Jaccard, cosine on TF-IDF) compare word overlap. Semantic methods (sentence embeddings) capture meaning even with different words. Choice depends on whether you need exact matching or meaning matching.

When to Use

Trigger conditions:

• Finding similar or duplicate documents in a collection
• Matching queries to FAQ answers or knowledge base entries
• Detecting plagiarism or content reuse

When NOT to use:

• For topic-level grouping (use topic modeling / LDA)
• For entity extraction from text (use NER)

Algorithm