What technique is used to estimate efforts for components using a hierarchical breakdown?

The technique that involves estimating efforts for components using a hierarchical breakdown is best described as top-down estimation. In this approach, the overall project or component is assessed first, and then that estimate is divided into subcomponents, allowing for a structured and systematic breakdown of the work involved. This helps in gaining an overview of the requirements and resources before delving into finer details.

Top-down estimation is particularly useful when there is limited data available or when a quick overall estimate is needed. This method can be effective in projects where a high-level view provides a sufficient basis for planning, particularly in the early stages of project development.

In contrast, bottom-up estimation focuses on estimating the labor and costs of individual components and then aggregating those estimates to determine the total project effort. Three-point estimation uses a statistical approach to estimate the likely duration or cost by considering optimistic, pessimistic, and most likely values. Analogous estimation relies on historical data from previous projects to inform the estimates for the current project. Each of these other techniques serves specific purposes but does not inherently use a hierarchical decomposition in the same way that top-down estimation does.