Understanding Schedule Progress Using Earned Value and Earned Schedule Techniques at Path-Level

Project monitoring and control is one of the core processes of effective production planning and scheduling. As part of this process, earned value management (EVM) is used to measure and forecast the duration and cost of production projects and activities. Using the EVM-based earned schedule (ES) value, the schedule variance (SV(t)) metric is calculated. This metric is further used to analyze the schedule progress. Based on this, potential schedule delays and slack times are calculated on both project-level and path-level. However, commonly in practice, they are derived from SV(t) values on the project-level. Moreover, the research on an individual path level or comparison of SV(t) on the project-level with the ones of the path-level is limited. This study proposes such a comparative analysis. The findings reveal misleading results regarding the project-level schedule analysis outcomes due to inconsistency in the computations from both path- and project-levels. For example, when the project-level analysis suggests a schedule delay the path-level analysis shows the project has no delay. Using a hypothetical production project, this study demonstrates how and when such inconsistent outcomes may arise. This study pioneers such concepts as “false positives” and “false negatives”. Based on its findings, the study discloses prospects for future research in this area.