問35
頻出度★★☆
システム要件定義の段階で，検討したシステム要件の技術的な実現性を確認するために有効な作業として，適切なものはどれか。
平成27年度 春期 ITパスポート試験 問35
ストラテジ系システム企画 › 要件定義
This question's explanation and your answers so far.
解説
問 35
Incorrectア
Creating a business model is the task of organizing and visualizing, with diagrams and the like, the flow of current or new operations, the data, and the relationships among organizations. It is used mainly in business requirements definition to clarify what the organization wants to do. It only depicts the shape of the business; it is not a means of verifying whether the technology that would implement those requirements can actually be used, so it does not confirm technical feasibility.
Incorrectイ
Calculating function points is a technique that quantifies a system's size from the number of its functions — inputs and outputs, screens, files, and so on — in order to estimate development effort and cost. What it yields is a rough measure of size and cost, not an answer as to whether the requirements can be achieved technically. It is useful for improving estimation accuracy, but it is a different task from the purpose asked about here.
- ウ
正解 The correct answer is ウ “Conducting prototyping”. Prototyping is a method in which a trial product (a prototype) is built early, before full-scale development begins, and is actually run so that it can be checked. What the question asks about is confirming whether the system requirements under consideration can really be achieved with technology, and desk study alone cannot determine whether the intended approach, performance, and technical elements truly hold up. So, if a small prototype is built and run during the requirements definition phase, technical feasibility — such as whether the technology to be adopted can carry out the intended processing, and whether performance and response time reach the required level — can be verified with a real working thing before large costs are incurred. A working prototype also helps align understanding with users and removes ambiguity in the requirements at an early stage, which likewise makes it a task well suited to the requirements definition phase. Therefore ウ is correct.
Incorrectエ
Gathering users' requirements is the task of collecting what is needed through interviews and questionnaires with users, at the stage before requirements definition or at its very entrance. What is obtained here is the requirements themselves, and whether the collected requirements are technically achievable must be confirmed separately. The question asks about a feasibility check aimed at the system requirements that have already been examined, so a task belonging to the requirement-gathering stage cannot be the answer.
ここがポイント
- Prototyping = a method of building a prototype early and actually running it. It is effective both for verifying technical feasibility and for aligning the understanding of requirements with users, and it is used in the requirements definition phase.
- Distinguish the roles of the tasks around requirements definition: creating a business model = visualizing and organizing the business; the function point method = estimating size, effort, and cost; gathering requirements = grasping user needs; prototyping = verifying feasibility and the requirements themselves.
用語