When planning a schedule with limited information, the project manager can use several techniques to identify tasks and estimate their durations:
* Rolling wave planning and an adaptive approach (A): Rolling wave planning is a form of progressive elaboration where the work to be accomplished in the near term is planned in detail, while the work in the future is planned at a higher level1. It is an iterative planning technique that allows you to plan for the future but focus on the immediate work2.
* Relative estimation to determine the task or deliverable sizes (B): Relative estimation is a technique used to estimate the size, effort, duration, or cost of work items by comparing them to other work items2. It is particularly useful when there is limited information available.
* Iterations and reviews to continuously keep adapting the plan : Iterative planning allows for adjustments and refinements as more information becomes available or circumstances change2. Regular reviews ensure that the plan remains relevant and effective.
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https://www.projectmanager.com/blog/project-management/planning-techniques-for-projects