Exam CBAP topic 1 question 87 discussion

BABOK v2 pg 170 Analogous Estimation Use of a similar project as the basis for developing estimates for the current project. It is used when little is known. Analogous estimating is often used to develop a rough order of magnitude (ROM) estimate, and is also known as “top-down” estimating. This is usually done at the beginning of the project or project phase and more detailed estimates follow as more is known.

The correct answer is D. Top-down estimate. A top-down estimate is an estimate based on past projects or experiences, where the estimator uses historical data to predict the cost and/or duration of the current project. This approach involves using high-level, overall project metrics from previous projects to estimate the current project's costs and duration. Top-down estimates are often used when there is limited information available about the current project, or when the project is similar to previous projects. The other options are not correct because: - A. Current estimate: This is an estimate based on the current project's specific details and requirements. - B. Past project cost: This refers to the actual cost of a previous project, rather than an estimate. - C. Past estimate: This refers to an estimate made in the past, rather than an estimate based on past projects.

D. Top-down estimate A top-down estimate is based on past projects to predict the current cost and/or duration of the current project. It uses high-level information from similar previous projects to estimate the overall cost and schedule​

Babok v2 Pages 170, 171 Top-down estimate is equal Analogous Estimate. Past Estimate Doesn't exists

I think D was selected as the answer in the context of estimating the current cost based on estimation performed early in the project life cycle when detailed information is limited and relies on high-level assumptions, analogous estimation, or historical data from similar projects.

They probably really meant B as it says that the estimation should be based on previous project costs and experience

Top Down: examining the components at a high level in a hierarchical Breakdown. None of the options are correct. Delphi estimation technique uses a combination of expert judgment and history.

Top down estimating approach deals with how long the project will take to completion then breaking them into various tasks. Bottom up deals with estimating how long it take each sub task to complete

Only top-down among the list is an estimation technique

Top-down: examining the components at a high level in a hierarchical breakdown.