Supervised Learning

You have labelled data and are trying to predict a label based on known features. Historical data predicts likely future events. Applies already learned concepts from a training dataset to a test dataset.

 

Supervised learning consists of 2 parts

  • Regression 
  • Classification

 

Learners

  • Weak  : Model which explains the variance more or less accurately
  • Strong : Model which explains the variance accurately

 

Bias – Variance Tradeoff

 

Bias : how much on average is my predicted values different from actual values. High bias is underfitting.

Variance : how different will predictions be, at the same point, if different samples are taken from the same population. High variance causes overfitting.

 

high bias = high (pred – act) = high error = underfit model

high variance = high sensitivity in changes in data = overfit model