Schedule Risk Model
Named uncertainty rubrics carry PERT-style duration multipliers — assign a band to each activity and contingency is embedded in the schedule without per-activity three-point entry.
Practical schedule risk analysis requires balancing statistical rigor with the reality of how much time estimators have to spend on model setup. Entering three-point duration estimates activity by activity on a 500-activity schedule is theoretically correct but operationally impractical. ProjectXL's rubric-driven model preserves the statistical foundation while making the setup fast enough to actually use.
How Rubrics Work
Project teams define named rubrics that represent their confidence classification scheme. Each rubric carries three multipliers — minimum, most-likely, and maximum — expressed as multiples of the activity's planned duration. A "Low Confidence" band might carry multipliers of 0.8, 1.0, and 1.6, reflecting the possibility of both schedule recovery and significant overrun. A "High Confidence" band might carry 0.9, 1.0, and 1.15, reflecting a tight range around the planned duration.
Once rubrics are defined, planners assign a band to each activity. The system derives the effective duration with contingency already embedded — no additional input required. The rubric definitions become the organization's auditable, reusable record of how uncertainty was characterized, rather than a pile of per-activity estimates that no one can trace back to a rationale.
Monte Carlo Output
The rubric multipliers flow directly into Monte Carlo simulation. Completed runs produce project-level confidence curves showing the probability distribution of finish dates, milestone-level target-date probability bands, and full task-level statistical outputs. Results can be saved as named SRA packages for historical comparison and downstream BI analysis.