personalized ranking model

• 최적화 방식이 세 가지로 나뉘어짐
  • pointwise
    • Pointwise approaches considers a single interaction at a time and train a classifier or a regressor to predict individual preferences.
    • 예시) matrix factorization, AutoRec
  • pairwise
    • Pairwise approaches consider a pair of items for each user and aim to approximate the optimal ordering for that pair.
    • 일반적으로 pairwise 방식이 ranking 업무에 더욱 적절하다.
    • 예시) BPR - Bayesian Personalized Ranking from Implicit Feedback
  • listwise
    • Listwise approaches approximate the ordering of the entire list of items, for example, direct optimizing the ranking measures such as Normalized Discounted Cumulative Gain (Normalized Discounted Cumulative Gain).
    • pointwise 나 pairwise 방식보다 복잡하며 계산 비용이 높다.