Linear Methods for Estimating Schedule Time Earned: Theory and Application
Publication: Journal of Management in Engineering
Volume 40, Issue 1
Abstract
This study introduces the term earned time (ET) for the class of linear methods which estimate the amount of project schedule time earned. Existing methods such as planned value (PV) rate, earned duration, and earned schedule are shown to be specific cases of earned time that use different linear rates to convert schedule variance in units of cost to units of time. An additional PV segment method is proposed that uses the linear rate of only the segment of the PV curve responsible for the schedule variance. The ET methods are examined theoretically and applied to three example projects to clarify their underlying assumptions. Five factors are found to guide the selection of a method for a given application: linearity, adherency, parallelism, stage, and status. The study contributes to theory by generalizing the concept of earned time and providing a new method for its estimation. The study is useful for practitioners seeking to apply ET methods and interpret their results.
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Data Availability Statement
Some or all data, models, or code that support the findings of this study are available from the corresponding author upon reasonable request.
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Information
Published In
Journal of Management in Engineering
Volume 40 • Issue 1 • January 2024
Copyright
© 2023 American Society of Civil Engineers.
History
Received: Apr 5, 2023
Accepted: Aug 7, 2023
Published online: Oct 13, 2023
Published in print: Jan 1, 2024
Discussion open until: Mar 13, 2024
ASCE Technical Topics:
- Benefit cost ratios
- Business management
- Case studies
- Construction engineering
- Construction industry
- Construction management
- Curvature
- Engineering fundamentals
- Financial management
- Geometry
- Linear functions
- Management methods
- Mathematical functions
- Mathematics
- Methodology (by type)
- Practice and Profession
- Project management
- Research methods (by type)
- Scheduling
- Value engineering
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