In this chapter, we design a fair user recommendation system for Mastodon, in step-by-step style.
First of all, we have to avoid the oldies effect. We can choose weekly, monthly, or other criteria with some finite duration.
Second, to avoid the shrink-wrap effect, we have better to use the number of boosts, rather than the numer of followers.
Now we find that, the weekly number of boosts is a fair criteria to recommend the users.
And one more thing, a reverse unfair criteria is fair. For example, we can imagine a rule that the user who has more than 100 followers is not recommended. This rule can be combinated with the weekly number of boosts criteria, which brings some additional fairness.
Now we get a design of a fair user recommendation system for Mastodon. Implementation is expected.