Chapter : Lesson 2

Episode 6 - Bias-Variance Tradeoff

face Josiah Wang

Summary:

  • Parametric models: Models with a fixed set of parameters.
  • Non-parametric models: Models are not constrained to be of a specific form or structure. The parameters may vary based on the training dataset.
  • Hyperparameters: Variables used to control a model.
  • Underfitting: Your model does not capture the structure from the dataset enough.
  • Overfitting: Your model has become too sensitive to small changes in your dataset.
  • High bias: Model is too constrained, causing underfitting to the dataset.
  • High variance: Model is too unconstrained, causing overfitting to the dataset.
  • Bias-variance tradeoff: Aim for the ‘sweet spot’ of low bias and low variance!
  • Occam’s razor: When more than one model that give similar performance, favour simpler models over complex ones.