A Comparison of the System Dynamics and Measured Mile Methods to Quantify Lost Productivity

Loss of productivity (LOP) is one of the most contentious and complex issues in construction claims and project performance assessment. Accurate quantification of LOP is critical not only for the substantiation and resolution of claims and disputes, but also for providing key inputs to cost control mechanisms and forensic schedule delay analysis. Among the numerous quantification approaches, the measured mile (MM) method and the system dynamics (SD) modeling approach represent two fundamentally different methodologies, one empirical, and the other simulation-based. This paper provides a comparative analysis of both methods, evaluating their strengths, limitations, data requirements, and situational applicability. Findings indicate that while the MM method, if properly implemented, is highly defensible in contractual disputes and relies on project-specific contemporaneous data, the SD approach has the capacity to offer deeper insights into modeling cumulative and systemic disruptions, especially in the context of complex or pervasive changes and impacts. The paper concludes with recommendations for method selection and potential for hybridization.