Lecture 01: Foundations of Machine Learning

January 10, 2024


Overview

This note introduces the basic concepts and core algorithms of machine learning.

Contents

1. Supervised Learning

Supervised learning aims to learn a mapping from inputs $X$ to outputs $Y$: \(f: X \rightarrow Y\) Common tasks:

  • Classification — discrete class labels
  • Regression — continuous values

2. Loss Functions

Mean Squared Error (MSE) for regression: \(L(y, \hat{y}) = \frac{1}{n}\sum_{i=1}^{n}(y_i - \hat{y}_i)^2\) Cross-entropy for classification: \(L(y, \hat{y}) = -\sum_{i=1}^{n} y_i \log(\hat{y}_i)\)

3. Model Evaluation

  • Training set — fit the model
  • Validation set — tune hyper-parameters
  • Test set — measure final performance

References

  • Machine Learning, Zhi-Hua Zhou
  • Pattern Recognition and Machine Learning, Christopher Bishop