A research study from the Data Science Team at Moz has sparked a lively debate, after suggesting that pages with a lot of Google +1s frequently ranked highly in SERPs.
They found that +1s were the second highest-correlating factor among pages that had achieved good rankings, beaten only by Page Authority.
This was supported by a similar study on Searchmetrics, which listed +1s as the most commonly seen feature of pages that ranked well. However, they chose not to delve deeper into why this might be the case.
Correlation v Causation
The debate here appears to be one of correlation versus causation. Do pages that rank highly attract a lot of +1s, or are they ranking well because Google can see they have a lot of +1s?
Moz previously saw a similarly passionate response to a post indicating a correlation between Facebook activity and rankings. On that occasion, Google rejected the notion that Facebook likes were a factor in their ranking algorithm, and Moz conceded that the apparent correlation was more likely to be due to factors such as quality content and links.
This time, they are suggesting a greater causal relationship at work, arguing that Google+ offers a much broader range of SEO advantages than other social sites such as Facebook and Twitter.
According to Moz, contributing factors include the speed at which Google+ posts are crawled and indexed, the number of followed links generated through shares and the way that Google+ posts share more features with a regular blog than similar stories added to Facebook or Twitter.
Google+ is Google's own social platform, so does it follow that doing well here will carry a lot of weight when it comes to rankings?
Matt Cutts Responds
As is often the case, Google webspam chief Matt Cutts quickly responded to the claims, rejecting the notion that +1s are used to determine rankings.
Posting on a Hacker News thread, he warned against treating correlation and causation as the same thing, and said he was searching for "the politest way to debunk the idea".
The gist of his argument is that content can generate both strong rankings and social shares naturally as a direct result of its high quality. Good content is likely to prompt others to share it, but Cutts is adamant that Google does not use +1s as a ranking signal.
Others have also pointed out that each share will point a link back to the post, and that these will carry a lot of weight as they have come from Google's own social platform.
More Questions Than Answers
Moz blogger Cyrus Shepard has since added a postscript to his original piece, saying that he accepts Cutts' point that Google does not take into account the number of +1s given to a post when determining rankings.
However, he still feels that there are benefits offered by Google+ that are not found on other social networks, and is hoping Google will clarify whether this is indeed the case.
Of course, as with most debates surrounding online content, one piece of advice continues to come to the fore. Rather than writing something that deliberately sets out to cultivate +1s, we should instead continue to focus on simply producing high quality content.
If we achieve this consistently, rewards such as social shares and ultimately higher rankings will be the natural result.