PUBLIC MARKS from Teulliac with tags engagement & analytics

As the social media analytics field is pretty knew, it’s really important to understand how the metrics are computed. Let’s take for example, one of Facebook’s core metric : the “Engagement Rate”.  What is supposed to be measured with the Engagement Rate ? “The Engagement Rate measures how well your Fans interact with your content”. That’s a common definition. What’s that supposed to mean ? If you have a 0.02% Engagement Rate, it means 0.02% of your fans have engaged with your content, isn’t it ?