Question: In a concise analytical response, explain the relationship among test-set size, confidence, and estimation of the system's final performance.

Sample answer: A test set is sufficiently large when it enables a confident estimate of the system's final performance. Thus, size is not treated as an isolated goal; it is evaluated according to whether the resulting final-performance estimate can be regarded with confidence.

Key points:

• The target is the system's final performance.
• The estimate should be confident.
• The test set must be big enough to support that confidence.
• Test-set size is tied to the purpose of performance estimation.

Rubric: A strong response clearly identifies final system performance as the estimation target, confidence as the required quality of the estimate, and sufficient test-set size as the condition supporting that confidence.