Rankings Correlation Study: Domain Authority vs. Branded Search Volume
Posted by Tom.Capper
A little over two weeks ago I had the pleasure of speaking at SearchLove San Diego. My presentation, Does Google Still Need Links, looked at the available evidence on how and to what extent Google is using links as a ranking factor in 2017, including the piece of research that I’m sharing here today.
One of the main points of my presentation was to argue that while links still do represent a useful source of information for Google’s ranking algorithm, Google now has many other sources, most of which they would never have dreamed of back when PageRank was conceived as a proxy for the popularity and authority of websites nearly 20 years ago.
Branded search volume is one such source of information, and one of the sources that is most accessible for us mere mortals, so I decided to take a deeper look on how it compared with a link-based metric. It also gives us some interesting insight into the KPIs we should be pursuing in our off-site marketing efforts — because brand awareness and link building are often conflicting goals.
For clarity, by branded search volume, I mean the monthly regional search volume for the brand of a ranking site. For example, for the page https://www.walmart.com/cp/Gift-Cards/96894, this would be the US monthly search volume for the term “walmart” (as given by Google Keyword Planner). I’ve written more about how I put together this dataset and dealt with edge cases below.
When picking my link-based metric for comparison, domain authority seemed a natural choice — it’s domain-level, which ought to be fair given that generally that’s the level of precision with which we can measure branded search volume, and it came out top in Moz’s study of domain-level link-based factors.
A note on correlation studies
Before I go any further, here’s a word of warning on correlation studies, including this one: They can easily miss the forest for the trees.
For example, the fact that domain authority (or branded search volume, or anything else) is positively correlated with rankings could indicate that any or all of the following is likely:
- Links cause sites to rank well
- Ranking well causes sites to get links
- Some third factor (e.g. reputation or age of site) causes sites to get both links and rankings
That’s not to say that correlation studies are useless — but we should use them to inform our understanding and prompt further investigation, not as the last word on what is and isn’t a ranking factor.
The Moz study referenced above used the provided 800 sample keywords from all 22 top-level categories in Google Keyword Planner, then looked at the top 50 results for each of these. After de-duplication, this results in 16,521 queries. Moz looked at only web results (no images, answer boxes, etc.), ignored queries with fewer than 25 results in total, and, as far as I can tell, used desktop rankings.
I’ve taken a slightly different approach. I …read more
Source:: Moz Blog