Question 1

What is schedule risk analysis?

Accepted Answer

Schedule risk analysis (SRA) is the practice of treating a project schedule as uncertain and computing the range of finish dates it could actually produce, usually with Monte Carlo simulation. Instead of one deterministic finish date, SRA gives probability-tagged dates such as P50 and P80, so commitments can be made at a known confidence level.

Question 2

What is a P80 date?

Accepted Answer

A P80 date is the date that 80% of simulated project outcomes finish on or before, leaving a 20% chance of finishing later. Epoch SRA treats P80 as the commitment level: its P80 is field-calibrated against replayed historical program actuals, while P50 is the median and deliberately styled as a reference, not a commitment.

Question 3

What is merge bias?

Accepted Answer

Merge bias is the effect where a milestone fed by several parallel paths tends to finish later than any single path predicts, because the milestone must wait for the slowest path in each simulated outcome. It is a structural property of networks that deterministic schedules systematically understate, and one of the main reasons Monte Carlo dates are later than CPM dates.

Question 4

How is Epoch SRA different from Full Monte?

Accepted Answer

Both tools run Monte Carlo schedule risk analysis. Epoch SRA runs as a task-pane add-in inside Excel, imports MS Project XML with the file's stored dates as the baseline, and prices risks from per-category impact priors that were field-calibrated against replayed historical space-program actuals, rather than asking the user to hand-estimate a distribution for every task. It also keeps a living loop: occurred events are logged as schedule mutations, believed versus actual magnitudes are recorded, and every run is seeded and reproducible.

Question 5

Does Epoch SRA import Microsoft Project files?

Accepted Answer

Yes. Export your plan from MS Project as XML (File > Save As > type: XML) and import it in the pane; the file is read locally and never modified. The import reproduces the file's stored dates as the baseline, translates all four link types (FS, SS, FF, SF) with working-day lags including leads, re-anchors summary links to leaf tasks, and is refreshable: re-importing keeps task ids stable by the file's own UIDs so risk mappings survive. Percent and elapsed-time lags have no exact working-day equivalent and are reported by name instead of approximated.

Question 6

What does Epoch SRA cost?

Accepted Answer

Three plans, per named user, ex-VAT: monthly at €119 per seat per month, annual at €990 per seat per year, and perpetual at €1,300 per seat plus €350 per year maintenance (€1,650 the first year, billed together). Every plan starts with a free 7-day trial in the add-in, and license keys are delivered by email within 24 hours of purchase.

Question 7

How does the 7-day trial work?

Accepted Answer

The trial is full-featured and starts on your first Compute – no signup, no card. After 7 days Compute is disabled but your workbooks, imports, and previously computed results stay fully accessible; entering a license key restores full function immediately.

Question 8

Is Epoch SRA only for space projects?

Accepted Answer

No. Epoch SRA is built from space-program experience and shaped for it – the risk taxonomy covers export-control delays, GFE deliveries, test failure and retest, and NCR/waiver loops, and the impact priors were calibrated against historical space-program schedules – so it is schedule risk analysis for space programs first. But the mechanics generalize: any program planned in MS Project or Excel with a costly finish date fits, and every category and prior is user-overridable per item.

Question 9

Can I use my own risk categories?

Accepted Answer

Yes. The register has two columns since v1.0.5.0: category is yours – free text, any taxonomy your program already uses, never validated, preserved verbatim through import and re-import. prior_class is separate: a dropdown of the eight calibrated failure patterns that picks which field-calibrated statistics price the risk. Your categories organize; prior_class computes. A risk without a prior_class is reported by name at compute, never guessed.

Question 10

What does ECSS-style 5×5 mean here?

Accepted Answer

ECSS-M-ST-80 is the European space standard for project risk management; its scoring convention is a 5×5 grid – likelihood 1–5 times severity 1–5, giving a banded risk index of 1–25. Epoch SRA's register uses that convention, and the scored likelihood and severity are what price each risk's impact in the simulation.

Question 11

What are alternatives to Full Monte?

Accepted Answer

Full Monte runs inside Microsoft Project; the main alternatives are Primavera Risk Analysis and Safran Risk at the enterprise end, RiskyProject as an affordable standalone desktop tool, and Epoch SRA if you want the analysis in Excel – on your MS Project XML, with field-calibrated priors and published pricing. Each is a different bet on where the work happens.

Question 12

Is there a low-cost alternative to Primavera Risk Analysis?

Accepted Answer

Yes. Primavera Risk Analysis itself is quote-based enterprise licensing, but RiskyProject publishes prices at $685–$979 per year and is a capable standalone tool, and Epoch SRA is €119/month or €990/year, Excel-native, with a 7-day trial that needs no sales call.

Question 13

Can @RISK do schedule risk analysis?

Accepted Answer

Yes – through its ScheduleRiskAnalysis (SRA) toolset, which imports Microsoft Project and Primavera P6 schedules into Excel for Monte Carlo analysis with probabilistic Gantt views (corrected 2026-08-06; an earlier answer understated the SRA toolset). The differences are elsewhere: Epoch SRA prices risks from field-calibrated priors with every percentile labelled by provenance, refuses-and-reports anything its import cannot faithfully translate, runs DCMA-style schedule checks on every Compute, and publishes per-seat prices with a no-contact trial.

Question 14

Is there a Lumivero schedule risk analysis product?

Accepted Answer

Yes (corrected 2026-08-06 – an earlier version of this answer wrongly said no standalone product of that name exists). Lumivero ScheduleRiskAnalysis (SRA) is a toolset within @RISK, shipped as part of the DecisionTools Suite, that imports Microsoft Project and Primavera P6 schedules into Excel and runs Monte Carlo on them, reporting standard and probabilistic Gantt charts with critical-path indices and a schedule audit report. Lumivero (formerly Palisade) has also acquired Risk Decisions, maker of the Predict! risk suite. For how it compares with Epoch SRA, see epochsra.com/resources/compare/atrisk/.

Question 15

Does Epoch SRA do cost risk?

Accepted Answer

Yes, since v1.1.0 (August 2026). Tasks take an optional cost_per_day (burn rate per working day of simulated duration) and fixed_cost; risks take an optional cost_impact added when they fire. Each simulated future prices its own cost from the same draw that produced its dates, so schedule results are unchanged. Outputs: cost P50/P80, a cost histogram, per-risk cost contribution, and a delay price – the expected cost per week of finish slip past P50, measured across the run's simulated futures at the user's rates. Cost numbers are derived from the calibrated schedule simulation through user-supplied rates; cost percentiles are never labelled field-calibrated – the backtest claim does not extend to money.

Question 16

Which calendar does Epoch SRA use?

Accepted Answer

Your file's. Since v1.2.0 the MS Project import reads the file's project calendar – working weekdays, day length, and holiday/extra-day exceptions within the schedule's span – and that calendar drives duration counting, lag conversion, every computed date, and what per-week means in the delay price. It lands in an editable ESRA_Calendar sheet; hand-built workbooks get the same sheet with a Mon–Fri default, and the file wins whenever a file exists. Stored dates are flagged only when non-working under the file's own calendar. Per-task calendar assignments are not simulated; each is reported by name and runs on the project calendar.

Question 17

Does Epoch SRA run DCMA 14-point checks?

Accepted Answer

Eight of the fourteen – and it says which. Every Compute runs schedule quality checks aligned with the DCMA 14-Point Assessment: logic, leads, lags, relationship types, high float, negative float, high duration, and the critical-path test are evaluated from schedule structure and CPM. The six points needing baseline, status, or resource data (hard constraints, invalid dates, resources, missed tasks, CPLI, BEI) each report not-applicable by name rather than a misleading pass. Results appear in a Schedule quality (DCMA-style) section in the pane and in ESRA_Results. The checks are informed by GAO Schedule Assessment Guide and NASA Schedule Management Handbook practices; no agency has reviewed or approved the product.

Question 18

Can I use a normal/Gaussian distribution?

Accepted Answer

No, deliberately. A normal distribution is symmetric and unbounded, so it puts probability below zero – in a schedule that means a risk firing and finishing the work early. Truncating it at zero would move its mean and every percentile away from the parameters shown, so the tool would display one distribution and simulate another, and a symmetric shape discards the asymmetry a three-point estimate exists to express. If you want the bell shape, choose Lognormal (bell shape, floored at zero): a rounded body, a hard floor at zero, and a right tail that runs past your maximum. Distribution choice is an optional override per risk; leaving it blank uses the calibrated triangular prior.

Choosing between Epoch SRA and Primavera Risk Analysis

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