See also the following links:

▎ENGLISH

Collaborative Filtering-Wikipedia
▸ https://en.wikipedia.org/wiki/Collaborative_filtering

Collaborative Filtering In Recommender Systems: Learn All You Need To Know
▸ https://www.iteratorshq.com/blog/collaborative-filtering-in-recommender-systems/

Item-based Collaborative Filtering : Build Your own Recommender System!
▸ https://www.analyticsvidhya.com/blog/2021/05/item-based-collaborative-filtering-build-your-own-recommender-system/

▎日 本 語

協調フィルタリングとは
▸ https://www.albert2005.co.jp/knowledge/marketing/recommendation_basics/collaborative_filtering

協調フィルタリング-Wikipedia
▸ https://ja.wikipedia.org/wiki/協調フィルタリング

協調フィルタリング入門
▸ https://www.slideshare.net/hoxo_m/ss-53305070