2.9. Classifiers

2.9.1. Co to jest Classifier?

A mapping from unlabeled instances to (discrete) classes. Classifiers have a form (e.g., decision tree) plus an interpretation procedure (including how to handle unknowns, etc.). Some classifiers also provide probability estimates (scores), which can be threshold to yield a discrete class decision thereby taking into account a utility function.

2.9.2. Schemat działania classifier

  1. Collect Training Data

  2. Train Classifier

  3. Make Predictions

../../_images/classification-spam.png

Figure 2.45. Schemat działania classifier. Wiadomości email przechodząc przez classifier są oznaczane jako spam, lub nie spam.