_______relationship model allows you to keep up with the latest happenings of any other user, even though that other user may not choose to follow you back or even know that you exist.

Social media analytics is the ability to gather and find meaning in data gathered from social channels to support business decisions - and measure the performance of actions based on those decisions through social media.
Some examples of social analytics metrics are click-through-rates, conversion rates, impressions per mille, engagement rate, and leads.