SEO Tips: Co-occurrence & Themes

By James Atkinson, LLB

Theme-based site analysis is now a major on-page factor in high rankings and social prominence is the major off-page factor. The algorithms look at how often certain words occur together on web pages.

This is called co-occurrence.

Essentially, Google takes a snapshot of every page in its index and analyzes them to discover which words and phrases tend to “co-occur” or be used together on the same page.

High co-occurrence of keywords (a significant number of pages using terms together in their text) indicates that the terms are closely related and part of a theme.

By doing this Google can tell that “dog food” and “dog health” are related because a significant percentage of web pages talk about both of them on the same page.

These keywords are no longer just isolated phrases – they have a relationship. They have context. They are part of a larger theme.

Next, Google will use its data on co-occurrence patterns to analyze the relevance of web pages in order to rank them. Google will analyze a site to determine the topic and how comprehensively it is covered.

Using co-occurrence, Google will judge how relevant your page is to the keyword “dog food” based on whether you also use other keywords that have high co-occurrence with “dog food” on your page and throughout your site.

If your page just uses the keyword “dog food” over and over in its text, Google will not judge you to be as relevant as if you used other related keywords such as: “dog health”, “dog diet”, “dog treats”, and so on.

Thus, the goal of theme-based SEO is to cover your topic more comprehensively than your competitors, covering more themes and supporting them well with other related themes and keywords to achieve maximum relevance.

Your site is analyzed and judged on how well it covers your theme.

Basically, Google will analyze your “dog health” site and all the keywords it uses, and how it uses them in relation to each other, against the co-occurrence patterns for those keywords that it has derived from its snapshot of all the other sites in its index.

If your site does not use the keywords that Google expects it to use, you will be judged as less relevant and you will not gain high search engine rankings. The reasoning behind the algorithms is that a dog health expert will write content that will naturally mimic the co-occurrence patterns and get ranked high.

That expert will naturally use a variety of different words related to the topic, rather than just using one keyword repeatedly.

Theme-based optimization rewards sites that demonstrate this expert understanding of their market: by using a variety of related terms to comprehensively cover their theme, and create a highly relevant and useful site for searchers.

Google is able to analyze your whole site and will determine how well you have covered your theme across the site.

And so I move to the technical aspects of your eBusiness which must be done correctly. There are two major technical aspects to consider:

1. Getting the Right Keywords / Themes with Research

I show how to DIY keyword research and more importantly why professional keyword research is best.

2. Structuring Your Site to Communicate to the Search Engines.

I show how to structure your web sites and content into folder silos.

SEO Tips > Themes, Not Keywords > Adwords and Relevance > Co-occurrence-and-Themes