Which statements are true about feature selection?

I. Feature selection chooses a subset of relevant features for use in the model building.
II. Feature selection is a reduction technique in dimensionality that creates new combinations of attributes.
III. The goal of feature selection is to come up with the smallest set of features that best captures the characteristics of the problem being addressed.

Correct Answer: I and III

II is about feature extraction. Feature selection includes and excludes the attributes that are present in the data without changing them.

III: The smaller the number of features used, the simpler the analysis will be. But of course, the set of features used must include all features relevant to the problem. So, there must be a balance between expressiveness and compactness of the feature set.