問38
頻出度★★★
ソフトウェアの品質評価の基準である品質特性には, 機能性, 信頼性, 使用性, 効率性などがある。機能性に関するテストとして, 適切なものはどれか。
平成22年度 秋期 ITパスポート試験 問38
マネジメント系システム開発技術 › システム開発技術
This question's explanation and your answers so far.
解説
問 38
Incorrectア
Verifying that the required performance, such as response time and processing time, is provided is a test concerning efficiency (a performance test). Efficiency is the characteristic that expresses how much processing capability is achieved relative to the resources and time used. It is a quality characteristic different from functionality, which asks whether the functions themselves are correct, so this choice is wrong.
- イ
正解 The correct answer is イ. Functionality is the quality characteristic that expresses whether software can correctly provide the functions requested by users, as stated in the requirements. A functionality test therefore verifies whether the software operates according to its purpose of use and the requirements definition (whether it returns output as specified for input as specified, and whether all necessary functions are implemented without omission). Choice イ, “Verify that it operates correctly according to its purpose of use and requirements”, is exactly this verification of functionality, and it is an appropriate description of functional testing, which checks whether the software works as required.
Incorrectウ
Verifying that the software can be used when needed and can recover quickly in the event of a failure is a test concerning reliability. Reliability is the characteristic that expresses how unlikely failures are and how easily the software recovers from them (availability and recoverability). It differs from functionality, which asks whether the software works correctly as required, so this choice is wrong.
Incorrectエ
Verifying that the software is easy for users to understand, learn, and operate is a test concerning usability. Usability is the viewpoint of operability, that is, how easily users can understand and use the software. It is a quality characteristic different from functionality, which asks whether the functions themselves are correct, so this choice is wrong.
ここがポイント
- Classification of software quality characteristics (the JIS X 0129 / ISO 9126 family): functionality = whether the correct functions are provided as required; reliability = whether the software is available when needed and can recover from failures; usability = whether it is easy to understand, learn, and operate; efficiency = whether performance such as response time and resource consumption is appropriate.
- Distinguishing the tests that correspond to each quality characteristic: functionality → functional testing (checking operation against the specification); efficiency → performance testing; reliability → checking availability and recoverability; usability → usability testing.
用語