Using Co-citation and Co-occurrence to improve your website’s SERPs

In a recent article about the external Google Keyword Tool, I wasn’t overly positive about Google, so I would like to use this article as an attempt to redeem myself in the eyes of the Great Google… Google does aim to provide the most useful, accurate and valuable information in its search results, and they make constant improvements to their algorithms to ensure this is the case.

Recently, SEO experts have been focusing on using anchor text on links to make their sites rank more highly. The idea being that Google will bump a site up in the rankings for a particular keyword if it finds an association between the keyword and the site – and a link on a keyword seemed a surefire way to achieve this.

In turn, Google has changed the rules again in order to provide the best information, and not just what the SEO experts want them to provide. They are looking for statistical correlations that they can use to judge the relevance and importance of a site. The experts are now saying that co-citation is the best way to improve your website’s rankings. This means that if website A mentions sites B and C, and site B has a high page rank, it will help site C. Conversely, if site B is a poorly ranked site or link farm, then it will negatively affect site C.


Co-occurrence is another buzzword. This occurs when a keyword is placed near to the link in website content. For example, website A mentions website B and the contextual phrases around the link contain the keyword. The proximity of the keyword and link indicate to Google that these are associated. Some experts feel co-occurrence is essentially the same concept as co-citation, whereas others argue it is different as it does not associate two sites via a third. However, both co-occurrence and co-citation stem from the idea that good quality sites with useful content will be naturally shared online.


Successful SEO is very much dependent on an organisation having a varied SEO strategy, with good content that others will want to share online. Link to other good sites, don’t link to bad sites, be active on social media, and most importantly – fill your website with great content.

(Graphics illustrating the difference between co-citation and co-occurrence are courtesy of The Search Engine Journal.)