PSD.12:5 - Archetypal Grounding
PSD.12:5.1 - An explicit reversal boundary for the pump comparison
Use the illustrative F and M slice from PSD.11: F costs 8 incremental budget units and loses 2 service hours with normal access or 3 with road loss; M costs 5 and loses 1 or 9 hours. N remains the baseline and S still has an unqualified whole-arrangement result. The following calculation tests only F against M; it does not close the wider candidate comparison.
For an illustrative analytical question, suppose a declared value model minimizes expected service-loss hours plus lambda times incremental budget units. Here lambda is an explicitly elicited value conversion, in service-hour-equivalent value per budget unit; it is not a measurement conversion or an unspoken public preference. Let p be the road-loss probability if a qualified probability model supports one.
Under those assumptions:
- F’s value loss is
2 + p + 8*lambda. - M’s value loss is
1 + 8*p + 5*lambda. - F has lower value loss precisely when
7*p > 1 + 3*lambda; equality is a tie.
For lambda = 0.5, the reversal is at p = 5/14, approximately 0.357. At p = 0.2, F and M give 6.2 and 5.1 respectively, so M is better under this model. At p = 0.6, they give 6.6 and 8.3, so F is better. These are invented sensitivity settings, not a forecast.
The source comparison supplied no probability. Therefore the valid return is the conditional boundary, not a claim that either setting is likely. If a probability model cannot be qualified, retain the scenario comparison instead of assigning equal chances.
A different declared test asks whether modeled service loss is at most 4 hours in both stated access conditions. F satisfies that illustrative test; M fails it under road loss. This is a different robustness criterion, not a hidden replacement for the value model. The four-hour cut is an example, not a domain standard. F’s result covers only those two modeled conditions.
The account returns the reversal boundary, the limited threshold result, the unresolved probability and value premises, and S’s candidate gap. Reachable assistance, wider property consequences, and protected conditions still require their direct results. None of the calculations authorizes a pump investment.
PSD.12:5.1.1 - A separate constructed delay-response question
Keep the preceding probability and value-reversal question separate. For this new illustration, fix a thirty-day service window and one access interruption. A stipulated model supplies the service-loss hours for F and M at three access delays; lower service loss is preferred. Each arrangement and all other modeled conditions stay fixed while delay varies.
| Access delay in days | F: service-loss hours | M: service-loss hours |
|---|---|---|
| 0 | 2 | 1 |
| 1 | 2.5 | 3 |
| 2 | 3 | 9 |
With x = 1 day and h = 1 day, M’s central response is 3 hours, its endpoint mean is (1 + 9)/2 = 5 hours, and D = 2 hours. F’s central response and endpoint mean are both 2.5 hours, so its D = 0. F has no midpoint gap at these three points; this does not establish a linear response between them.
Under the separately declared four-hour service-loss criterion, M’s two-day response of 9 hours fails. F satisfies that criterion at the three stated points only. Neither endpoint mean is an expected real loss without a probability basis, and a central response below four hours does not settle the endpoint test.
The useful return is the finite response difference, M’s failure condition and the remaining model and coverage limits. F’s additional investment and the feasibility of any alternative access protection still need their whole-configuration comparison. If the stipulated model lacks support for real use, retain the calculation as conditional or illustrative; do not report an established pump-performance result. No additional observations or investment are authorized by it.
PSD.12:5.2 - What would change a development recommendation?
In the illustrative ninety-day organization case, I is internal development with covered service duties and H is a mixed human–tool arrangement. The earlier supplier bounds, 12–18 and 8–20 service-loss hours, do not establish a robust ordering.
Suppose a qualified joint operating model now supplies two admissible conditions within those bounds:
| Condition | I: service-loss hours | H: service-loss hours | Supported comparison on this coordinate |
|---|---|---|---|
| Required handoff coverage is present. | 14 | 10 | H has less service loss. |
| The specified handoff coverage is absent. | 16 | 20 | I has less service loss. |
The robustness result locates a reversal in the whole arrangement’s coverage condition. It does not attribute the difference solely to human learning or model quality. The useful next question is the feasibility and persistence of that exact coverage under the proposed allocation, not a generic demand for a higher AI benchmark or another course test.
If that result can be obtained within the decision window, the adviser can return it as an information priority with its cost and limits. If not, the recommendation remains conditional or retains both directions. A service model for another team or model version does not close this holder-specific boundary.
PSD.12:5.3 - Cheap non-use and honest stop
A current analysis already proves the same service comparison throughout the relevant parameter interval, and the only proposed new computation repeats interior points without challenging another assumption. Reuse the result. If the untested issue is instead a missing causal or safety premise, stop the robustness calculation and obtain that direct result; more parameter samples will not supply it.