Third Annual PMCOS College of Fellows Meeting
January 10-12, 2019
The Breakers, Palm Beach, Florida
Panel: Improving on the Predictive Accuracy of P80 Dates
Panelists: Gui Ponce de Leon, PE, PMP; Bruce Stephan, PE, PMP; Tarek Bahgat, PMP
The CPM algorithm’s ability to develop bounding early/late dates using activity durations and logic was a new scheduling paradigm that has sustained CPM as the scheduling method of choice since 1957. Regrettably, when used in Monte Carlo probabilistic scheduling, CPM develops only x,000 instances of the early schedule, and therefore only the early completion distribution curve.
This Panel has two objectives. First, to reveal how the GPM probabilistic scheduling algorithm, by allowing activities to float in every iteration, develops x,000 instances of both the statistical early and late schedules, unveiling early/late bounding completion distribution envelopes from which practitioners can infer more realistic 80% confidence level completion aka P80 dates.
Second, with this compelling finding, to ask fellow practitioners (who are keenly aware of the vagaries of risk schedule analysis) whether we should reconsider relying on CPM risk assessment tools that tend to promote optimistic P80 dates based only on the early completion distribution. The hoped-for outcome is a path forward toward more realistic schedule risk analysis results.
Gui Ponce de Leon, PhD, PE, PMP
Dr. Gui Ponce de Leon is one of our nation’s foremost planning and scheduling experts. His professional experience includes roles as investor’s developer, construction manager, program manager, and EPC contractor planner/scheduler. Dr. Gui has continually pioneered innovations in project management throughout his 45-year career. With GPM, he is on a quest to transform scheduling from a “black box” task performed by specialists to stakeholder-centric processes that promote collaboration, enhance stakeholder interaction, and inherently result in reliable schedules.
Bruce Stephan, PE, PMP
Bruce Stephan is a nationally recognized licensed civil engineer with more than 30 years of experience on complex medium, large, and mega engineering/construction projects. Mr. Stephan has held progressively responsible positions in the construction of water, transportation, and power infrastructure industries ever since. His distinguished career includes public service, general contracting, and consulting nationally and internationally. His award-winning experience includes design-build, integrated project, CM-GC, and CM at-risk delivery methods on public capital improvement programs.
Tarek Bahgat, PMP
Tarek Bahgat, a Project Controls Manager at APTIM, has extensive experience in construction management, project management and controls, risk management, value engineering, and cost estimating and controls. He has provided relevant services on transit, infrastructure, power plants, water/wastewater facilities and large hotel construction programs.