ITPEC FE Morning October 2019 Question 53
Which of the following is the technique for estimating activity durations where past information is statistically analyzed and various coefficients are determined?
Explanation
Parametric estimate — past data is analysed statistically to find coefficients, which are then applied to the parameters of the new work.
A parametric estimate models duration or cost as a function of measurable parameters. Historical records give the coefficients, for example hours per screen or per 1,000 lines of code, often found by regression; multiplying them by the new quantities gives the estimate. Its accuracy depends on the quality of the historical data and the model. COCOMO is a well-known parametric model.
Answer (c)
Why not others:
- •(a) Analogous estimate — takes the actual duration of a similar past project and adjusts it by judgment; one comparable project, no statistically derived coefficients
- •(b) Bottom-up estimate — breaks the work down into small work packages, estimates each and adds them up
- •(d) Three-point estimate — combines optimistic, most likely and pessimistic values, for example (O + 4M + P) ÷ 6 in PERT, to allow for uncertainty
Key rule: One similar past project is analogous; coefficients from historical statistics times size is parametric; a sum of detailed parts is bottom-up; three scenarios is three-point.
Project Management · AI-written, may contain errors
This question comes from an official ITPEC past paper. ITPEC Practice is an independent study tool and is not affiliated with ITPEC. See the official FE past-paper collection or Report an issue.