Question: In a short analytical response, describe the proper role of a test set and name the kinds of decisions it should not drive.

Sample answer: A test set is meant to estimate how well the final model will perform on unseen data. It should not be used to choose between learning algorithms or to tune hyperparameters. Those decisions should be made using training or validation data, while the test set is reserved for final evaluation.

Key points:

• The test set is for estimating generalization performance.
• It should not determine which learning algorithm is chosen.
• It should not determine hyperparameter settings.
• Model selection and final evaluation serve different purposes.

Rubric: A strong response clearly identifies the test set as an evaluation tool, excludes both algorithm choice and hyperparameter tuning, and separates selection from final assessment.