Topical Authority
Theoretical FoundationsA measure of website thematic authority calculated as Topical Coverage multiplied by Historical Data. Coverage consists of three pillars: Vastness (breadth), Depth (thorough treatment), and Momentum (publishing pace). Simply writing content isn't enough; you must also 'earn' it with user signals (clicks, impressions, time on page).
Example of a garden furniture store: removing content about grass and flowers shifted the centroid to 'garden furniture' and rankings improved. Less can be more. In AI Search, Topical Authority determines whether content gets considered as a citation source at all. Domain charts look like 'stairs': flat, flat, JUMP at Core Update, meaning SEO implementation effects are only visible at the next algorithm update.
In practice, build Topical Authority systematically — minimum 20 pages to start (bulk publishing), CORE first, OUTER later, and monitor Site Focus Score to ensure the centroid doesn't drift.