Effort Estimation Template - Pert

PERT Effort Estimation Project ID/ Name: Project Type : Prepared By/Date : Reviewed By/Date: Approved By/Date: Revision Draft

Date

Revision History Rational for Changes

Summary of Changes

PERT Effort Estimation # 1 2 3 4 5 6

Core Process Requirement Definition Design (HLD + LLD) Coding + Unit Testing Integration Testing System Testing (QAT) Project Management & Configuration Management Total Estimate in Hrs Contingency Total Estimate in Hrs Total Estimate in mandays

7

Task ID Task name / Module Name 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26

Percentage used 10% 15% 35% 10% 20% 10% 5%

Total person 0 days 0 0 0 0 0 0 0 0 0

Task/Activity - Coding & Unit Testing Estimated in Hrs Minimum Likely (Optimistic) (Realistic)

27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 Total Hrs (Coding + Unit Testing)

mated in Hrs Maximum (Pessimistic)

PERT (Weighted Average) 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Effort Estimation using WBS and PERT Technique Guidelines PERT stands for Project Evaluation and Review Technique --- a project and time management developed by NASA and now part of the PMBOK standard. – Based on idea that estimates are uncertain – Therefore uses duration ranges – And the probability of falling to a given range – Uses an “expected value” (or weighted average) to determine durations Steps: 1. The job/work is broken into smallest tasks/activities and list them in the " task column" 2. Make sure the person estimating the work understands the difference between effort (person/hours) and duration (length of time to completion, and is answering in effort, not duration. 3. For each task, ask the following questions: – What is the shortest amount of time it might take, if it goes really well? (Input minimum box) – What is longest time ,it might take, if problems come up? (Input maximum box) – What is it likely to take? (Input likely box) 4. Calculate the PERT (weighted) average as (optimistic + 4*realistic + pessimistic)/6, to give a centered average. 5. Final estimate is calculated Notes: Each task from the WBS should be estimated at the lowest level of detail. Ideally, the person providing the minimum/likely/maximum figures should be the person who will do the work. If not, then numbers can be adjusted based on the different work speed of the estimator and the actual worker assigned. Field definitions From WBS Task #: Copied from WBS. in format 1.2.3.4 Task name: Copied from WBS Times (estimated in hrs) Minimum: The shortest reasonable time to do the job Likely: The time it would normally take to do the work Maximum:The time it would take if problems arose (not worst case, but worst likely case) Calculation PERT Statistical average PERT Time = ((min)+4*(likely)+(max))/6 (This gives an average weighted toward the middle. 6 is the divisor because you are averaging a total of six times, one minimum plus four likelies plus one maximum). Final estimate: Final estimate is calculated

f the PMBOK

to completion,