PSD.10:4 - Solution
Connect each material uncertainty to the exact claim and decision it can change. Use a representation justified by the available knowledge, retain dependencies and limits, and return a bounded claim, discriminating question, narrowed use, or blocker.
PSD.10:4.1 - Start from a comparison that could change
Name the subject, configuration, horizon, receiving question, considered alternatives, and result currently being claimed. Ask which premise could change their consequences, relative standing, eligibility, or the need for a probe. If the alternatives themselves are unclear, return that candidate question.
Use PSD.5’s model account only where its evidence or assumptions bear on this same configuration and horizon. The model can expose an uncertainty without resolving it. A current qualified direct result can supply the same premise without requiring a model-building exercise.
Check both relative and absolute consequences. An uncertainty shared by all alternatives can leave their order unchanged yet show that none meets a required service or safety condition. Do not dismiss it as irrelevant merely because it is not a ranking discriminator.
PSD.10:4.2 - Represent what is unknown at its actual kind
Choose a form that answers the live question without claiming more knowledge than exists.
| Available basis | Useful representation | Limit that must remain visible |
|---|---|---|
| Qualified stochastic model or elicited probabilistic judgement. | A distribution or probability statement tied to its event, population, conditions, and horizon. | Calibration, sampling, elicitation, model assumptions, and applicability still matter. Confidence in the analyst is not the event probability. |
| Supported bounds but no distribution. | An interval or set of admissible values. | An interval is not a uniform distribution; state what supports its endpoints and what lies outside its claim. |
| Several materially different models or future conditions. | Conditional claims under named models or scenarios. | Their count or frequency in an ensemble does not supply real-world likelihood. |
| A decisive absent result or unrepresented mechanism. | The exact missing claim and the comparison it prevents. | A blank cell is neither zero effect nor equal performance. |
| Incompatible interpretations, preferences, or authority claims. | Attributed alternatives and the unresolved interpretation or judgement. | Statistical uncertainty reduction alone cannot reconcile them. |
These are use choices, not a universal taxonomy of uncertainty. Different forms may coexist in one account. Distinguish a physical or behavioral variability claim from uncertainty about its model, data, or applicability whenever the distinction changes the return.
If a probability is useful but unsupported, state the conditional comparison it would enable and identify the needed basis. Do not assign equal probabilities to scenarios simply to make an expected-value calculation run.
PSD.10:4.3 - Qualify the relied-on claims
For each decision-bearing source result, keep the claim, subject, supplying result kind, source edition or effective window, assumptions, evidence, intended use, exclusions, and material dissent recoverable. Use A.10 for the actual bounded reliance question; its disposition does not establish the source claim’s truth or authorize the decision.
Ask whether the evidence concerns the same holder, intervention, environment, and horizon. Separate observed results, forecasts, expert judgements, and unsupported extrapolations. An observation of a benefit is not automatically a causal effect; the direct causal or domain Method supplies that support.
Use an already-qualified result within its limit. If a consequential cross-practice result is still missing, A.15.9 supports the smallest request or blocker. Do not ask another practice to “remove the uncertainty”; ask for the specific claim, bound, interpretation, or test that could change this comparison.
PSD.10:4.4 - Preserve dependency and model disagreement
Recover shared data, common causes, conditional assumptions, and other dependencies when they affect the consequence comparison. Evidence repeated by several models is not several independent confirmations. Expert or model aggregation needs its own justified Method; the number of voices alone does not determine a probability.
Keep incompatible assumptions separate until a direct result supports their combination. For example, a scenario with a failed access route and a scenario with a functioning route can test different claims; combining their most favorable outcomes produces no realizable case.
Where alternative models disagree, identify the overlapping proposition and what explains the difference: scope, input, representation, mechanism, or unresolved evidence. A new measurement may discriminate the models; sometimes the honest answer is that the present use must retain both. Do not turn disagreement into a narrow average solely because a downstream table expects one number.
PSD.10:4.5 - Form a discriminating question
Write the question in terms of its possible consequences for the current return:
For this subject and horizon, establish whether this premise lies inside the region supporting alternative A, outside it, or remains unresolved; state the evidence and limits needed for that use.
The requested result may concern eligibility rather than ranking. It may also show that no available alternative works, that a different formulation is needed, or that only a reversible analytical use is supported.
Name a feasible observation, calculation, interpretation, or comparison that might answer the question, its supplying practice, and the relevant time or access limit. If no feasible inquiry can answer before the decision window closes, say so. Do not promise that more data will settle structural ignorance.
This pattern identifies decision-linked questions. PSD.12 can later examine reversals and information priorities; C.11 or the direct choice owner decides whether an actual next probe is worth its cost and authorized. A question with high uncertainty is not automatically the best probe.
PSD.10:4.6 - Return the strongest supported claim and no stronger
A short return states:
- what claim about which alternatives is supported, for which configuration and horizon;
- its uncertainty representation, source limits, and dependencies;
- what different answer could change the comparison, admissibility, or receiving use;
- the exact unanswered question or blocker; and
- what source, observation, candidate, value, or configuration change would reopen the account.
Return “unchanged within the tested bounds” only when those bounds cannot alter the stated result. Return a conditional or narrowed claim when support covers only part of the use. If a required protected-condition premise is unsupported, preserve the direct domain stop rather than compensating with confidence elsewhere.
Recognition may begin with one unexplained estimate. Consequential reliance requires the evidence and assurance demanded by the direct practice, including its independent checks when applicable. This pattern supplies no universal evidence score or acceptable uncertainty threshold.
When a relied-on source actually changes, revalidate the affected use. Use G.11 for a currentness question and A.10.1 when the changed claim must be traced through several actual uses. Do not discard unrelated claims merely because they share a source file.