Are you staying on topic (in a correct way)? Is TopicalAuthority really a thing? Can it be measured? How? What insights on that topic can we gain from the Google leak? Do semantics relate to user behavior…?
One of the noteworthy elements I discovered while analyzing the Google Warehouse API leak were the siteFocus and siteRadius scores. They are kind of essential to understand the concept of topical authority (or however you call it).
So, what’s it all about and why are we here.
Recently I digged a little bit more into Google API Leak documents. I presented my thoughts to my SEO team takaoto.pro. Then I went to Chiang Mai SEO Conference and met guys like Erfan Azimi and Adam Collins and had a chance to chat with Koray Tugberk GUBUR once again. And it made me thinking more (again) about topical authority in context of new things I’ve learned recently like siteRadius and siteFocus.
Content
What is siteFocus?
SiteFocus measures how strongly a website concentrates on a specific topic. It evaluates the overall consistency of the content. A higher siteFocus score means the website maintains a clear, strong focus without wandering into unrelated subjects.
What is siteRadius?
SiteRadius indicates the distance between individual page embeddings and the overall site embedding. It shows how far each page’s content deviates from the website’s main topic. This helps Google determine whether a page aligns with the site’s central theme or strays into unrelated areas.
source: https://hexdocs.pm/
Why covering the whole topic is important?
Whether you follow Koray’s framework, other semantic SEO concepts, or advocate more straightforward and simple approach, one thing is clear: websites that stick closely to a specific topic get rewarded.
BTW, check fresh Tomasz Tymiński’s interview with Adam Collins from Chiang Mai. It’s about keyword mapping and they mention the idea of aligning to user intent in context of general keyword strategy:
So, you get rewarded for publishing content on a certain topic. However, to earn this “bonus,” you need a well-structured site and content that’s easy for Google to understand—which requires at least a basic grasp of NLP logic in their algorithms.
On the other hand you shouldn’t go to far and write like a robot. There’s something called PQ (pageQuality) in documents that leaked from Google. One of the aspects that it focuses on is “effort”. Google is verifying how easily each document could be replaced by the content generated by LLM on certain topic. This is why they insist on “added value” in Helpful Content guidelines and earlier in Review Update documentation.
Misconceptions and tips
From my experience, I’ve noticed some common misconceptions in this area (I also made some of these mistakes). Let’s look at some of them closer.
I used to look at topical authority as a metric that could be scaled, kind of infinitely. Now, I see it more as a binary value: Google either recognizes your site as staying on-topic or it doesn’t. That said, there’s still room for competition in this space.
Metrics like siteRadius and siteFocus are calculated using embeddings (on page and website level), possibly with methods like cosine similarity, BERT embeddings, Doc2Vec, or TF-IDF. I admit that I don’t know the exact methodology, but these metrics seem scalable within certain limits, such as a cosine similarity range of -1 to 1. Or assuming some topical alignment from +0 to 1.
Some websites can hold stronger topical authority than competitors. But achieving this isn’t about covering a broader range of topics but about staying narrowly focused on your core entity and satisfying the main user intent. In other words, your goal should be to comprehensively cover the narrow topic you specialize in (and keep it updated) —not spread yourself thin across an entire category.
I once thought building topical authority meant creating encyclopedic coverage of an entire field. For example, if you sell chandeliers, I assumed you’d need to write about every aspect of interior design. But that’s not true. Instead, focus specifically on your niche— chandeliers. Cover FAQs, buying intent, and various contexts related to them. You could write about curtains, rugs, furniture, or maybe some luxury goods and events, but only in the context of matching them with chandeliers. Keep the spotlight on your core entity.
Going too broad, like creating generic advice about “how to design a living room,” “how to decorate a kids’ room,” or “how to style an office,” increases your siteRadius and decreases your siteFocus.
Also remember, that the home page while targeting mainly branded keywords also should clearly say, what is the main topic of the whole website. I think that it’s reasonable to assume, that it can be used as a reference point to metrics like siteRadius and siteFocus.
Semantic metrics vs user signals
One essential element of building topical authority is creating a logical structure for your website. This involves linking similar pages together in a cohesive way, often referred to as a “silo with satellites” structure. By clustering related keywords and grouping pages with high pageSimilarity, you can create a network of interlinked content that forms one solid, coherent entity. This entity should align closely with your site’s core theme and the main user intent.
However, it’s crucial to remember that user behavior is becoming increasingly important in SEO. A perfect semantic structure alone won’t guarantee success. Great content quality isn’t enough as well. Users attention span is narrowing down, so focus on CTA’s, contextual links and leading your customer to expected endpoint (micro or main conversions).
Focus on understanding user intent, map out the customer journey, and integrate this knowledge into your internal linking strategy. Combine logical content clusters with links that guide users naturally through the site, ensuring a seamless and intuitive experience.
Key Takeaway:
Stay focused! On topic… and on user’s needs.
Disclaimer – these documents from the leak aren’t precise, so we don’t have access to many details. My post is a brief comment based on what I understood from this documents and some trustworthy summaries. I just combined and confronted it with my experience. If you don’t agree with something, found counterarguments (for example in Google Patents or your own case studies) – drop me a message through the form below – I may edit the original post and add your perspective.
Photo credit: Michał Mączka (Linkhouse). From the left: Igor Wiśniewski (Digital PR Studio), Tomasz Tymiński (Linkhouse) and Szymon Słowik (that’s right, it’s me).