Click-through rate (CTR) measures the share of users or impressions that produce a click on a presented link, recommendation, or control. It offers a practical signal of whether displayed content appears relevant enough to explore. section 4.4.2 section 7.2.3
CTR is useful but incomplete. A high recommendation CTR suggests relevance, while conversion rate more directly connects recommended items to purchases and revenue. Engagement signals such as dwell time, browsing time, and interactions add context. section 4.4.2
Use CTR to support ongoing evaluation and optimization:
- Monitor whether users click top-ranked search results; low CTR can indicate that results do not match search intent. section 7.2.3
- Compare recommendation strategies through A/B tests, while checking conversions and broader engagement rather than optimizing clicks alone. section 4.4.2
- Track CTR continuously because new documents, changing user behavior, or evolving products can alter performance after launch. section 4.4.2 section 7.2.3
Low search CTR
If users repeatedly search for “feature comparison” but rarely click the returned results, the low CTR signals a likely relevance problem and points toward refining retrieval or ranking. section 7.2.3
