Combining EDM and EVM: a proposed simplification for project time and cost management

Earned value management (EVM), a technique mainly used to manage project cost, was developed during the second half of the twentieth century by an agency of the USA government. It was enriched, at the beginning of the current century, with an extension named earned schedule (ES) (Lipke, 2003), which added to EVM the capability to manage the project schedule.In 2014, earned duration management (EDM), a novel, and monetary value free technique for project schedule management, was proposed by Khamooshi and Golafshani (2014). Earned duration (ED), the project schedule indicator from EDM uses only activity dates and durations from EVM, and aims at replacing ES.  By not using cost as a proxy for time, ED overcomes one of the most criticized aspect of ES.This paper intends to (i) compare ED with ES to learn some fundamental lessons, (ii) propose the combination of ED and planned value (PV) from EVM to produce an EDM-based project-level earned value (EV〗^d), and (iii) assess the adequacy of 〖EV〗^d as an alternative to earned value (EV) from EVM in project time and cost management.  The comparison between the project real cost and both EVM and EDM-based independent estimates at completion, on a set of real projects, was the vehicle for assessing the adequacy of 〖EV〗^d  as a viable alternative to EV.Workload avoidance by replacing activities earned value calculations with the simpler and more consistent determination of the activities earned durations, and the enhanced visibility of potential schedule problems caused by lower cost/duration ratio activities, are benefits that 〖EV〗_d offers to project managers.