Hands-On Machine Learning with C++

Bias

The bias is a prediction characteristic that tells us about the distance between model predictions and ground truth values. Usually, we use the term high bias or underfitting to say that model prediction is too far from the ground truth values, which means that the model generalization ability is weak. Consider the following graph:

This graph shows the original values with black dots, the values used for validation with green dots, and a line that represents the polynomial regression model output. In this case, the polynomial degree is equal to one. We can see that the predicted values do not describe the original data at all, so we can ...