Reminder: Three different spaces that are
easy to confuse
Weight-space
Each axis corresponds to a weight
A point is a weight vector
Dimensionality = #weights +1 extra dimension for the loss
Data-space
Each axis corresponds to an input value
A point is a data vector. A decision surface is a plane.
Dimensionality = dimensionality of a data vector
“Case-space” (used in Bishop figure 3.2)
Each axis corresponds to a training case
A point assigns a scalar value to every training case
So it can represent the 1-D targets or it can represent the
value of one input component over all the training data.
Dimensionality = #training cases