Which method is typically used for calculating projected costs in project management?

Bottom-up estimating is a method used for calculating projected costs in project management because it involves breaking down the project into smaller components or work packages, allowing for more detailed and accurate estimations. This method requires input from team members who are familiar with the specific tasks and associated costs, thereby enhancing the reliability of the estimates.

By assessing each individual element of a project, project managers can accumulate these costs to form an overall project budget. This granular approach helps identify potential areas for cost overruns and allows for better planning and resource allocation. Additionally, bottom-up estimating can lead to a clearer understanding of the project's scope and improve communication among team members regarding expectations and individual responsibilities.

In contrast, other methods such as top-down estimating provide a broader overview but may lack the granularity needed for precise cost estimation, while methods like expert judgment and parametric estimating rely on experience and established relationships rather than detailed analysis of project specifics.