Hello, one of the developers here. What you said is not quite accurate, as our ranking algorithm will still rate websites with high popularity/traffic (Alexa Rank) even with no facebook shares / referring domains or any other metrics. They will not reach such high positions, but they will be ranked.

Makes sense. Following this thread, what do you think would be a good ranking strategy besides Alexa rank and social shares?

Definitely backlinks, number of referring IPs/domains is very big indicator of website Authority.

Besides that, UX factors like bounce rate, session duration, etc. are very good indicators as well.

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