Probabilistic Risk-Based Estimating

Desktop application for rigorous, Monte Carlo-powered cost and schedule risk analysis of highway construction projects.

Improving the reliability of project estimates one analysis at a time

Download Free Trial Purchase License — $29.99

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PRBE Simulation Results - Distribution Charts showing probability distributions for project cost and completion date

Powerful Risk Analysis Made Accessible

PRBE automates the NHI Course 134205 methodology, bringing rigorous probabilistic analysis to every project team.

🎲

Monte Carlo Simulation

Run thousands of iterations with configurable parameters, convergence monitoring, and reproducible results via random seed control.

📊

Distribution Charts

Interactive PDF and CDF charts for total cost (current year and year-of-expenditure) and project completion date with percentile analysis.

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Tornado & Sensitivity Analysis

Identify which risk variables have the greatest influence on cost and schedule using Spearman rank correlation tornado charts.

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Tail Driver Analysis

Understand which risks drive extreme outcomes with fire rate comparison, excess contribution metrics, and plain-language interpretations.

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Market Conditions Modeling

Model Better-Than-Planned, As-Planned, and Worse-Than-Planned market scenarios with probability-weighted cost multipliers.

🔗

Correlation Analysis

Define cost-cost, schedule-schedule, and cross-type correlations using a Gaussian copula for realistic multi-variable modeling.

📅

Inflation & YOE Adjustment

Convert current-year costs to year-of-expenditure dollars with customizable inflation tables and phase-segment predecessors.

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Risk Register & Reporting

Comprehensive risk register with customizable views (Brief, Standard, Full), CSV/Excel export, and print-optimized layouts.

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Import & Export

Import risks from Excel templates, export risk registers, and backup/restore complete projects for transfer or archival.

See PRBE in Action

A modern, browser-based interface that's powerful yet intuitive. All data stays local on your machine.

Project Management

Organize multiple projects with an intuitive dashboard. Create, duplicate, and manage projects with full backup and restore capability.

  • Create unlimited projects (licensed)
  • Export and import project backups
  • Duplicate projects for scenario analysis
  • Organized sidebar navigation
PRBE Project List - Home page showing project cards

Risk Identification

Define risk events with probability distributions, dependency types, and detailed documentation. Import risks directly from Excel templates.

  • Triangular, BetaPERT, Uniform, and Normal distributions
  • Visual distribution editor with PDF/CDF preview
  • Mutually inclusive/exclusive dependency modeling
  • Excel template import for workshop data
PRBE Risk Identification page with risk table

Contingency Analysis

Get clear, defensible budget recommendations with detailed statistics for current-year and year-of-expenditure costs.

  • Risk-based contingency calculation
  • P10 through P90 percentile tracking
  • Budget recommendation with confidence level
  • Printable summary reports
PRBE Contingency Analysis and Summary Statistics

Sensitivity & Tail Drivers

Pinpoint exactly which risks matter most with tornado charts and tail driver analysis, so teams can focus mitigation where it counts.

  • Spearman rank correlation tornado charts
  • Top 3 favorable and adverse tail drivers
  • Fire rate and excess contribution metrics
  • Phase-segment drill-down capability
PRBE Tornado Chart showing sensitivity analysis

Built on Proven Methodology

PRBE implements the National Highway Institute (NHI) Course 134205 framework for risk-based estimating in transportation projects.

1

Define Structure

Set up segments, phases, and cost categories that match your project scope.

2

Enter Base Estimates

Input cost and schedule data with variability ranges for each phase-segment.

3

Identify Risks

Add risk events with probability distributions, correlations, and market conditions.

4

Run Simulation

Execute Monte Carlo analysis and review distribution charts, tornado diagrams, and tail drivers.

Simple, Perpetual Licensing

Start with a free 90-day trial. Your license never expires — the app keeps working forever.

New License

$29.99
One-time payment • No subscription

Perpetual use of any PRBE build released in your first 12 months. The app keeps working forever on versions you're entitled to.

  • Full Monte Carlo simulation engine
  • Unlimited cost & schedule risk analyses
  • Distribution curves & tornado diagrams
  • 12 months of free updates from purchase date
  • Renew anytime for $14.99 to extend another 12 months
  • Email support during your active coverage window
Purchase — $29.99

Free 90-day trial included with download. Up to 3 projects during trial.

Renewal

$14.99
Half price • Optional, no auto-renew

Already a customer? Extend your upgrade coverage another 12 months for half price. Renew anytime — there's no lapse penalty.

  • Extends upgrade coverage another 12 months
  • Access to all new PRBE releases during the window
  • Email support during your renewed coverage
  • No auto-renew — you control when to extend
  • Renew anytime, even after your window expires
Renew — $14.99

Your Machine ID is visible in the top bar of the app once it is licensed.

Frequently Asked Questions

Everything you need to know about PRBE licensing.

What exactly am I buying?

A perpetual license to any PRBE build released within the 12 months after your purchase. The app you install never stops working — there's no subscription, no phone-home, no auto-renew.

What happens after 12 months?

Your installed PRBE keeps working forever. If we release a newer version and you want it, renew for $14.99 to get another 12-month upgrade window. If you don't care about new versions, do nothing — your current build is yours.

What do I lose if I don't renew?

Only access to newer releases. No features get disabled, no projects become inaccessible.

Can I use my license on a new computer?

Licenses are bound to a Machine ID. Email support and we'll reissue at no charge.

Do you offer refunds?

Yes — contact us within 30 days if PRBE isn't working for you.

Is there a subscription?

No. Renewals are optional and manual. You control when (or whether) to extend.

I bought PRBE before April 2026. Does this change anything for me?

No. Customers who purchased before the upgrade-window model was introduced keep lifetime access to all future versions — no renewal needed, ever.

About PRBE

PRBE was created by Michael Smith following his retirement from the Federal Highway Administration in 2023, where he spent 32 years advancing quantitative risk assessment for highway infrastructure projects.

The application implements the methodology taught in the National Highway Institute (NHI) Course 134205, making rigorous probabilistic cost and schedule estimating accessible to project teams without requiring specialized statistical software.

PRBE is a standalone desktop application that runs entirely on your local machine. It launches a local server and opens in your web browser, requiring no cloud connectivity or external dependencies. All project data remains on your computer, ensuring complete data privacy and security.

Compatible with Microsoft Windows. Chrome, Edge, or Firefox recommended for the best experience.

Contact & Support

Michael.Smith935@gmail.com
678-702-7769