In the past week, I explored different ideas, talked to the faculty, and found more papers to read. I found lots of interesting paper related to my personalized skin care product recommendation idea. I found out that using content-based filtering to recommend products might be helpful, and I could modify the algorithm to have better performance.
Some papers I found useful include:
 Recommender System By Grasping Individual Preference and Influence from other users
 Recommendations System for Purchase of Cosmetics Using Content- Based Filtering
 Item Clustering as An Input for Skin Care Product Recommended System using Content Based Filtering
These papers gave me an idea for what algorithm to use for the recommendation system and how to modify it according to my need. Some of the research was done using five skin types, but I’m thinking to increase it to 16 or more.