PSD-CARD-01 — Turn a contested situation into a usable recommendation

• Situation: A municipal committee needs advice on a pre-season pumping arrangement. Operations staff emphasize capacity, residents raise unequal protection, and responders question safe access and deployment.
• Question: What can the inquiry recommend while preserving those differences and the committee’s investment authority?
• First useful result or blocker: Attributed formulations and a usable inquiry boundary; then a conditional comparison whose omissions remain visible in the recommendation.
• Start with: PSD.1 for the receiving question and authority boundary. If these are adequate, enter at the missing participation, formulation, model or comparison result.
• Stop or return: Return the supported advice or its limitation through PSD.13. Reopen the dependent model, alternative, scope or recommendation when a material concern or premise changes. The committee retains the later choice.

The constructed flood-pump application begins with an independent inquiry team preparing a return for the committee. PSD.2 discovers affected people and concerns beyond those able to attend. PSD.3 preserves different formulations: insufficient capacity, unequal protection, fragile maintenance and unsafe deployment. Their consequences inform the PSD.4 boundary: compare the pre-season pumping arrangements while keeping material downstream effects and mobility constraints visible. Long-term relocation remains outside this inquiry.

That boundary changes the modeling question. PSD.5 keeps nominal pumping capacity separate from whether people can reach assistance and whether a mobile pump can arrive when roads fail. PSD.6 compares a capacity-only calculation with a bounded combination of attributed inquiry and conditional technical analysis. The combination is useful only if its contributions can be obtained and their subjects, conditions and meanings can be joined. PSD.7 lets participants correct the claim “the pumps protect the district”: a capacity result does not answer the separate access question. A concern map supplies questions for comparison, not numerical weights.

PSD.8 retains the current arrangement, fixed pumps, mobile pumps and a still-incomplete staged direction. The following slice compares only fixed and mobile pumps. Its loss and cost figures are illustrative units, not measured impacts or a complete investment account.

With an assumed road-loss probability p and cost weight λ, the illustrative lower-is-better scores are 2 + p + 8λ and 1 + 8p + 5λ. PSD.9 keeps the trade-off premise separate from protected conditions; PSD.10 retains the missing basis for p. PSD.11 supplies the comparison, and PSD.12 exposes its reversal: fixed pumps score lower when 7p > 1 + 3λ. At λ = 0.5, mobile pumps score lower for p = 0.2, but fixed pumps do for p = 0.6. Neither input is established for the committee’s decision by this calculation.

The PSD.13 return therefore retains the conditional comparison while withholding a whole-investment ranking. Access, assistance and protection conditions remain unqualified; the baseline and staged direction were not disposed of by the two-row calculation. A further result is requested through A.15.9 only if its obtainable contribution warrants the burden. Even resolving road access would not by itself settle the value trade-off.

Suppose the committee authorizes a study, and a qualified source then establishes that mobile deployment is unavailable during the required window. PSD.14 returns to the mobile alternative and its consequence premises; this is not a reason to insert a convenient value of p. Preserve the earlier conditional calculation as such, but do not use it as the current investment basis. If a newly affected group reveals an omitted consequence, return to the boundary as well. Study authorization still leaves pump procurement to its own decision.