This is our proprietary influencer authority or credibility score. If an influencer gets lots of engagement on their posts on the topic from other influencers talking about the same topic, or they get mentioned a lot by others in relation to the topic, they will get a high score. Engagement matters here but we also consider who the engagement is from.
'Topical Authority' is a normalised score of relevant influencer interactions on the topic searched. So for any topic-based search the top score will always be 100 and other scores will be given a score of 0-100 based on how their authority compares with the top influencer.
An influencer might get a high topical authority score on a topic even if they don't post much on the topic and don't get much engagement on their own posts. If other influencers who are authoritative on the subject @mention the influencer or link to their blog in the context of the topic this will confer authority on the topic to that influencer - for example mentioning them as the author of an article or quoting something they've said.
The Interactions that are included in the algorithm are mentions, retweets and replies on Twitter or links between articles for blogs.