Movie Recommender System
The Problem
Recommendation systems drive an estimated 35% of e-commerce revenue and 80% of Netflix viewing hours. But most tutorials stop at "cosine similarity on a toy dataset" without exploring what actually makes recommendations good — or building something a real user can interact with.
I wanted to go deeper: build a dual-approach system that combines content understanding with collaborative signals, and ship it as a live product people can use.
The Approach
- Content-Based Filtering: TF-IDF vectorization on movie descriptions, genres, and cast, combined with cosine similarity to find movies that share characteristics with the user's favorites
- Collaborative Filtering: User-item interaction matrix factorization to surface patterns like "people who liked X also liked Y"
- Hybrid Ranking: Weighted combination of both approaches for more robust recommendations that handle cold-start gracefully
- Interactive Frontend: Streamlit interface where users select a movie and instantly see personalized recommendations with posters, ratings, and genres
Key Results
- Content-based approach captures genre/cast similarities that collaborative filtering misses
- Collaborative approach surfaces non-obvious connections between movies
- Hybrid combination outperforms either approach alone on relevance metrics
- Fully productionized with interactive web interface
Business Value
Revenue Impact: Recommender systems are responsible for 35% of Amazon purchases and 80% of Netflix viewing. This project demonstrates the full pipeline from algorithm design to deployment. Passion Signal: Built this because I love movies and wanted to solve the "what to watch next" problem for myself — then shipped it so anyone can use it.