Suggestion for Recommender system algorithm for 3 sets of entities
I am building a model to recommend logistic providers to merchants on an e-commerce platform. There are approx. 100k merchants and 20 logistic providers, so scaling is not very important here.
Currently, everytime a customer makes a purchase from a merchant, the merchant will need to select a merchant from the list of 20 to ship the goods to the user. Some merchants always choose the cheapest shipping options, while some have their own personal preferences. The location of the customers may also play a part in deciding which logistic provider to use.
Most recommendation systems I know of are user-item pair. My problem involves 3 parties: merchant, user (or user location), logistic providers. Can anyone recommend any high level structure or framework to solve this problem? Thanks in advance.
Topic recommender-system
Category Data Science