---
# System prepended metadata

title: RECOMMENDATION SYSTEM

---

# RECOMMENDATION SYSTEM

1. Non reciprocal
2. Reciprocal


## Non reciprocal

Books, Movies, Musics

Known Algorithm
1. Content based filtering
2. Collaborative filtering & Matrix factorization
3. NN ????

### Content based filtering
![](https://i.imgur.com/jpU97i8.png)

問題
1. Hand engineered feature
2. make recommendations based on existing interests

### Collaborative filtering

![](https://i.imgur.com/GG0suMC.jpg)


### Matrix factorization

![](https://i.imgur.com/2IEGD1M.png)
![](https://i.imgur.com/8uladno.png)

問題
1. Cannot handle fresh items
2. Hard to include side features for query/item

using SVD or NN


https://www.researchgate.net/publication/221140972_RECON_A_reciprocal_recommender_for_online_dating
https://github.com/asinghvi92/Dating-Recommendation-System
https://arxiv.org/pdf/2011.12586.pdf
https://arxiv.org/pdf/1501.06247.pdf
https://arxiv.org/pdf/1807.01227.pdf