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🎯 Introduction to Recommendation Systems Series v1.0

From Collaborative Filtering to Deep Learning Recommendations

📖 Total Learning Time: 5-6 hours 📊 Level: Intermediate to Advanced

Learn implementation methods for personalization, from the fundamentals of recommendation systems to collaborative filtering, matrix factorization, and deep learning-based recommendation techniques

Series Overview

This series is a practical educational content consisting of 4 chapters that enables you to learn the theory and implementation of Recommendation Systems from basics to advanced levels in a step-by-step manner.

Recommendation Systems are machine learning technologies that suggest optimal products, content, and information based on user preferences and behavioral history. Analyzing user-item similarity through collaborative filtering, extracting latent factors through matrix factorization (SVD, ALS), feature matching through content-based filtering, integrating multiple algorithms through hybrid methods, advanced personalization through deep learning (Neural Collaborative Filtering, DeepFM, Two-Tower Model) - these technologies are implemented in global platforms such as Amazon, Netflix, YouTube, and Spotify, and have become essential skills in all fields including e-commerce, video streaming, music streaming, and news distribution. This series provides practical knowledge necessary for real-world applications, including understanding evaluation metrics (RMSE, Precision@K, nDCG), addressing cold start problems, and validating recommendation accuracy through A/B testing.

Features:

Total Learning Time: 5-6 hours (including code execution and exercises)

How to Learn

Recommended Learning Order

graph TD A[Chapter 1: Recommendation System Fundamentals] --> B[Chapter 2: Collaborative Filtering] B --> C[Chapter 3: Content-Based and Hybrid] C --> D[Chapter 4: Deep Learning Recommendations] style A fill:#e3f2fd style B fill:#fff3e0 style C fill:#f3e5f5 style D fill:#e8f5e9

For Beginners (no prior knowledge of recommendation systems):
- Chapter 1 → Chapter 2 → Chapter 3 → Chapter 4 (all chapters recommended)
- Duration: 5-6 hours

For Intermediate Learners (with machine learning experience):
- Chapter 1 → Chapter 2 → Chapter 4
- Duration: 4-5 hours

Strengthening Specific Topics:
- Recommendation System Fundamentals and Evaluation Metrics: Chapter 1 (focused learning)
- Collaborative Filtering and Matrix Factorization: Chapter 2 (focused learning)
- Content-Based and Hybrid Recommendations: Chapter 3 (focused learning)
- Deep Learning Recommendations: Chapter 4 (focused learning)
- Duration: 70-90 minutes/chapter

Chapter Details

Chapter 1: Recommendation System Fundamentals

Difficulty: Intermediate
Reading Time: 70-80 minutes
Code Examples: 8

Learning Content

  1. What are Recommendation Systems - Definition, business value, major application areas
  2. Types of Recommendation Tasks - Rating prediction, ranking, Top-N recommendation
  3. Evaluation Metrics - RMSE, MAE, Precision@K, Recall@K, nDCG
  4. Dataset Structure - User-item matrix, implicit and explicit feedback
  5. Cold Start Problem - Approaches for new users and new items

Learning Objectives

Read Chapter 1 →


Chapter 2: Collaborative Filtering

Difficulty: Intermediate
Reading Time: 80-90 minutes
Code Examples: 10

Learning Content

  1. Principles of Collaborative Filtering - User similarity and item similarity
  2. User-based CF - User similarity, neighborhood selection, rating prediction
  3. Item-based CF - Item similarity, scalability
  4. Matrix Factorization (SVD) - Latent factor model, dimensionality reduction, rating prediction
  5. ALS (Alternating Least Squares) - Handling implicit feedback

Learning Objectives

Read Chapter 2 →


Chapter 3: Content-Based and Hybrid

Difficulty: Intermediate
Reading Time: 70-80 minutes
Code Examples: 9

Learning Content

  1. Content-Based Filtering - Item features, TF-IDF, profile construction
  2. Feature Engineering - Categorical features, text features, numerical features
  3. Hybrid Recommendation - Integration of collaborative filtering + content-based
  4. Weighted Integration - Linear combination, switching, cascade
  5. Cold Start Solutions - Utilizing content information

Learning Objectives

Read Chapter 3 →


Chapter 4: Deep Learning Recommendations

Difficulty: Advanced
Reading Time: 80-90 minutes
Code Examples: 10

Learning Content

  1. Neural Collaborative Filtering (NCF) - MLP, GMF, NeuMF
  2. Embedding Layers - Learning distributed representations of users and items
  3. DeepFM - FM + Deep Neural Network, feature interactions
  4. Two-Tower Model - User tower, item tower, efficient inference
  5. Transformer Recommendations - Self-Attention, sequence recommendations

Learning Objectives

Read Chapter 4 →


Overall Learning Outcomes

Upon completing this series, you will acquire the following skills and knowledge:

Knowledge Level (Understanding)

Practical Skills (Doing)

Application Ability (Applying)


Prerequisites

To effectively learn this series, it is desirable to have the following knowledge:

Required (Must Have)

Recommended (Nice to Have)

Recommended Prior Learning: