Topic-Embeddings (Focus/Radius)

Google computes a kind of 'topic map' from the entire text content of a website (embedding, a mathematical vector representation of the topic space). siteFocusScore measures how sharply the site's topic field is defined. siteRadius measures how widely it scatters thematically. A small radius means a tightly focused site. The system measures thematic consistency, not subject-matter competence.

The system learns self-supervised from the site's language use, meaning from the actual text of all pages, without human labels. The resulting vectors feed into NSR as a focus vector.

siteEmbeddings is the vector representation of the site's topic space. siteFocusScore shows how sharply the topic field is outlined. siteRadius shows how widely the site scatters in topic space: a small radius means a focused site. [B fields]

Expertise and Authority are indirect ('flanking'). A focused weather site is more likely to be perceived as a weather expert than one that also offers recipes and travel reports alongside weather. But focus alone doesn't substitute for quality: it is a multiplier.

A clear thematic focus feeds the focus score positively. Content far outside the thematic core can raise the radius. For international expansions or new brands: plan thematic coherence from day one.