問51
頻出度★★★
プロジェクトのスケジュールを短縮する方法について説明したものはどれか。
平成21年度 秋期 ITパスポート試験 問51
マネジメント系プロジェクトマネジメント › プロジェクトマネジメント
This question's explanation and your answers so far.
解説
問 51
Incorrectア
Changing from the waterfall type to the spiral type is a choice of development process model; it changes how well the project copes with changing requirements and how quality is assured. Because each iteration adds reviews and re-planning, the duration does not necessarily become shorter, so this is not a way to shorten the schedule.
Incorrectイ
Tasks that are not on the critical path have slack (float), so changing their order does not change the length of the longest path. The overall duration is set by the tasks on the critical path, so touching non-critical tasks produces no shortening effect.
- ウ
正解 ウ is correct. A project's duration is determined by the length of the longest path from start to finish (the critical path). If tasks that were planned to run one after another are changed to run in parallel, task durations that used to be added up in series now overlap, the path becomes shorter, and the overall duration shrinks. This technique is called fast tracking, and together with crashing (speeding up the tasks themselves by adding staff or cost) it is one of the two representative schedule-shortening methods. Note, however, that a task which should normally wait for the previous task to finish is started early, so the risk of rework increases.
Incorrectエ
Adjusting the workload so that it stays roughly constant over the whole period is resource leveling, which flattens peaks and prevents members from being overloaded or left idle. Its purpose is stable use of resources, and the duration may even become longer; it is not a shortening method.
ここがポイント
- A project's duration is determined by the length of the critical path. To shorten it you must act on the tasks on the critical path; moving tasks that have slack has no effect.
- There are two representative shortening techniques: fast tracking (running sequential tasks in parallel so their durations overlap, which raises the risk of rework) and crashing (adding staff or cost to speed up the tasks themselves, which raises cost). Resource leveling is not a shortening technique.
用語