That’s the TL;DR of it, but read on for a deeper look at some individual topic areas and how we came to these figures. View the full study here.
Definitions and Limitations
To better understand the data, let’s detail some definitions first:
Correlation coefficient: A linear measure of the correlation between two variables. A value of 0 indicates no association between the two variables. A value greater than 0 indicates a positive association, and a value less than 0 indicates a negative association.
Organic share of voice (SOV): Organic SOV is a metric that represents how much organic traffic a site receives vs. the other sites in that sector for a set of high-traffic keywords. It considers keyword volumes, click-through rates, ranking position, and SERP features. The final SOV is expressed as a percentage of that keyword set’s total available search volume. So if your SOV is 25%, you’re winning 25% of the clicks for that set.
Topical link relevance: A score that shows the relevance of a keyword or topic to the entire document text or range of pages analyzed – in this case, the text on each page that links back to the sites we analyzed. The higher the number, the more relevant a topic. A score of 0 means that the topic was not relevant at all.
Unique linking domains: The total number of unique domains that link back to each site.
Domain Authority (DA): A ranking score developed by Moz that predicts how likely a website will rank on SERPs. A DA score ranges from 1 to 100, with higher scores corresponding to greater visibility.
Limitations
This study relies on correlation and thus has limitations. Please note that correlation ≠ causation, and because Google historically does not comment on studies, or reveal precisely how the ranking algorithm works, we’ll likely never find causation. However, based on patents mentioning the use of topical relevance in combination with the findings of the correlation studies, we can be confident in the validity of the data.
Relevance vs. Link Volume
As an example, let’s look at the bathroom sector. When looking at hundreds of keywords related to bathrooms like bathroom mirrors and bathroom ideas, we found that this sector has over 1.8 million searches per month, with leading home brands competing for share of voice.
After analyzing the backlink profile and relevance score, we then calculate a correlation with that brand’s share of voice to determine if there is any connection between this metric and organic visibility.
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Anything below zero has a negative correlation, so there is no connection.
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Anything over zero has a positive correlation.
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The higher the correlation, the stronger the relationship between the metrics and organic visibility.
