Imagine you are in charge of creating a new way to sort the messages a person sees in his social media feed (Facebook news feed, Twitter feed, etc.). You have access to the entire social network. Also assume that users have the opportunity to rate how much they trust their friends (but not all will do so).

a. How will you use trust to sort the news feed?

b. How will you deal with cases where people have not rated the trustworthiness of their friends? How can you estimate trust in those people?