Lecture 16 – Bias and Variance

Presented by Isaac Schmidt

Content by Isaac Schmidt, Andrew Bray, Suraj Rampure, Ani Adhikari

Important: You may want to review Lecture 3 for a refresher on random variables.

Video Quick Check
16.0
Introduction.
16.1
The data generation process, and the assumptions we make when choosing a model.
16.1
16.2
Continuous random variables. Expectation of a function of a random variable. Bias, revisited.
16.2
16.3
Variance of a random variable. Linear transformations of variance. Covariance and correlation.
16.3
16.4
Bias and variance in modeling. Simulation of different models with different samples. Components of prediction error.
16.4
16.5
Risk. Decomposition of model risk into the components of prediction error.
16.5
16.6
The Bias-Variance decomposition. Reasons and remedies for the different components of error.
16.6
16.7
Overfitting and underfitting. Complexity, and the bias-variance tradeoff.
16.7