Recommendation System

Content-Based Filtering

Approaches

• Classification

• Regression

Collaborative Filtering

Approaches

• Model-based

  • Matrix Factorisation

• Memory-based

  • user-user

  • item-item

Problems

Cold Start Problem

• Representative based

  • use a subset of items and users that represent the population.

• Content-based

  • use side information such as text, social networks, etc.

• Bandit

  • consider the exploration vs exploitation tradeoff in new items.

• Deep Learning

  • recent methods that try to solve some of the issues tackled above but using a black box.

Solution - Content + Collaborative = Hybrid Filtering

Grey Sheep Problem

Solution - Content + Collaborative = Hybrid Filtering

Evaluation

Metrics-based Evaluation

Human-based Evaluation