When to use it
Use it for initial screening when precise distributions are not defensible.
When to be cautious
Ordinal scores are not money or calibrated probabilities; multiplying category numbers can distort rankings.
Apply it
Screening score = probability category × impact category
Multiplying ordinal category labels does not produce expected loss or a defensible monetary reserve. Record the underlying scenario.
- Define the event, horizon and consequence scale.
- Assess likelihood and impact with evidence and uncertainty.
- Escalate unacceptable consequences even when their score appears modest.
An example in practice
A rare safety-critical failure receives senior attention even when a numerical score would place frequent minor defects above it.
Source & credit
Standard estimating practice; the cited guide documents use rather than claiming invention.
GAO: Cost Estimating and Assessment Guide
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