The TikTok users in an implicit community might not explicitly acknowledge they are a part of the community. They only share a few common interests or they are following the same influencers on TikTok. 

 

a) Suggest and apply machine learning methods to identify TikTok user groups among a large base of users based on features and conditions that differentiate sample users from one another. 

 

b) Identify at least three challenges in the proposed machine learning methods and discuss the solutions to overcome them.