This topic will cover the basics of machine learning, including definitions, types of machine learning (supervised, unsupervised, and reinforcement learning), and common applications.
Introduction to Machine Learning
Key concepts, terminology, and foundational ideas
| Definition | Core Idea |
|---|---|
| Machine Learning (ML) is a sub‑field of artificial intelligence that enables computers to learn patterns from data and make decisions or predictions without being explicitly programmed for each task. | Instead of hard‑coding rules, an algorithm infers a function f that maps inputs X to outputs Y from examples. |
| Paradigm | Goal | Typical Tasks | Example Algorithms |
|---|---|---|---|
| Supervised Learning | Learn a mapping from inputs to known labels. | Classification, regression | Linear regression, Decision trees, SVM, Neural networks |
| Unsupervised Learning | Discover hidden structure in unlabeled data. | Clustering, dimensionality reduction, density estimation | K‑means, Hierarchical clustering, PCA, Autoencoders |
| Semi‑Supervised Learning | Combine a small labeled set with a large unlabeled set. | Improved classification when labeling is expensive | Self‑training, Graph‑based methods |
| Self‑Supervised Learning | Create surrogate labels from the data itself. | Representation learning for vision, NLP | Contrastive learning, Masked language modeling |
| Reinforcement Learning (RL) | Learn a policy that maximizes cumulative reward through interaction. | Game playing, robotics, recommendation | Q‑learning, Policy gradients, Deep Q‑Network (DQN) |
| Transfer / Multi‑Task Learning | Leverage knowledge from related tasks to improve performance. | Domain adaptation, few‑shot learning | Fine‑tuning pretrained models, Multi‑head networks |
Data
Model
Loss / Objective Function
Optimization Algorithm
Evaluation Metrics
Deployment & Monitoring
1️⃣ Define the problem → 2️⃣ Collect & explore data → 3️⃣ Preprocess & engineer features
↓ ↓
4️⃣ Split data (train/val/test) 5️⃣ Choose model & loss
↓ ↓
6️⃣ Train (optimize) → 7️⃣ Validate & tune hyper‑parameters
↓
8️⃣ Test on held‑out data → 9️⃣ Deploy
↓
🔁 Monitor → Update (re‑train) as needed