HCD.18:5 - Archetypal Grounding
HCD.18:5.1 - A complete small specification for active effort and elapsed turnaround
A teacher is preparing a short introduction for readers who can read clock times, add intervals, and use a calculator. The promised work is to separate task effort from turnaround and compare consumed person-time with available person-time. The material stays available. A teacher may ask a corrective question after the first answer. Independent first recognition and supported correction are recorded separately.
Call the following specification Time-use S1. Its decision is whether the material supports this bounded introduction with the declared teacher contribution, and what to repair before relying on it. The object is the handout’s explanation, examples, task, and usable correction support, not a learner’s durable capability or the visual quality of an uninspected export. Qualification holds while these tasks, audience prerequisites, support, and time-accounting meanings remain unchanged.
The subject criteria are stipulated before an attempt: active effort sums the named person’s active intervals; elapsed turnaround spans first start to handoff; exclusive active intervals are not double-counted; simultaneous work by different people is added as person-time; a resource comparison uses the same population and unit on both sides.
| Task derived from the promise | Required contribution and discriminating error |
|---|---|
| Interrupted report | One person works on a report 09:00–09:30 and 11:30–12:00, with incident work 09:30–11:30. Return report effort 60 person-minutes, incident effort 120 person-minutes, report turnaround 180 clock-minutes, total effort 180 person-minutes, and incident share 120/180. Calling report effort 180 exposes the rival rule. |
| Concurrent people | A works on X 09:00–10:00; B works on Y 09:00–11:00; both are available 09:00–11:00. Return consumed effort 3 person-hours, available effort 4 person-hours, and elapsed window 2 hours. Compare 3 with 4, not 3 with 2. |
| Correction and continuation | Preserve the first report answer, then ask which intervals contain report work and which belong to the incident. Ask the reader to correct or defend the answer and apply the distinction to the concurrent-people task. A repeated answer without a reason does not show that feedback enabled correction. |
These tasks are not inferred from the handout’s headings. The interruption distinguishes two time concepts; the concurrent case distinguishes person-time from clock duration. Both are necessary to the stated promise.
Time-use S1 selects six characteristics. It uses the profile’s ordinal repair/use anchors, with higher values better for this use. For the supported-use conclusion, every selected property must be at least 4 on the evidence required below. This is S1’s conservative local decision rule, not an HCD floor. No averaging compensates a failed required property. Missing evidence returns “insufficient evidence for supported use”; it does not prohibit a controlled probe designed to obtain that evidence.
| Selected characteristic | Evidence required for 4 in S1 | What distinguishes the neighbouring repair or resilience judgement |
|---|---|---|
| Subject validity | Inspect the explanation, example, task, key, and correction against the stipulated meanings; challenge the interruption and population denominators. | One bounded incorrect unit label with otherwise consistent uses calls for 3; a wrong central rule propagated through the explanation and use calls for 2. For 5, demonstrate an additional useful boundary treatment, such as separating waiting from other-task work without corrupting either quantity. |
| Task and dependency coverage | Trace both task families and their prerequisites to actual material or accessible declared support; inspect that each needed operation is supplied. | A missing usable return for one supplied operation is bounded repair; absence of the concurrent-person operation needs a connected addition. For 5, show useful coverage of a consequential further case, such as unequal availability, while preserving the original promise. |
| Explanatory sufficiency | Inspect the grounds linking intervals, quantities, and comparison; obtain reader work under the declared prerequisite and support conditions that reveals how the reader recovers those grounds. | One missing transition differs from rebuilding the active/elapsed explanation chain. For 5, the reader can use the supplied explanation on an additional consequential variation, with its source contribution and assistance visible. |
| Example discrimination | Apply the correct and rival rules to the supplied examples. At least one example must distinguish interruption and one must distinguish aggregate person-time from elapsed duration, in material or the declared accessible support. | An isolated misleading example amid a sufficient discriminating pair differs from an example set compatible throughout with the rival rule. For 5, an additional boundary contrast prevents a further identified misapplication. |
| Task and criterion validity | Independently solve the tasks; test the key against a correct alternative and the named rival errors. Equivalent units and justified exact or rounded shares are accepted. | A key’s bounded omission differs from a task–criterion chain that elicits or rewards the wrong quantity. For 5, the criterion demonstrably discriminates a further consequential error without rejecting a valid alternative. |
| Feedback and continuation support | Inspect the available feedback and observe a first answer followed by the declared question, an explained correction or justified retention, and the changed task. Record the teacher’s actual contribution. | A missing next-task return differs from a support arrangement that cannot expose or correct the central discrepancy. For 5, an additional relevant difficulty can be handled through the declared support without supplying the next answer wholesale. |
The remaining profile families do not become automatic extra scores. In this bounded case, semantic representations and language are inspected where they carry the selected explanations and criteria; no separate alternative export, long narrative route, or changing subject edition is promised. If one of those conditions changes, revisit the selection.
For each coordinate, S1 returns the value or named missingness, the inspected material passage and task, the criterion and actual response, source inspection versus reader evidence, available and actual help, adjacent-value grounds, and repair reach. A 4/5 judgement without its required observation is blocked. An observed subject error can still support a lower value without waiting for a learner to reproduce it.
HCD.18:5.2 - Contrasts that test what the specification can conclude
A deficient handout, M0, says that time spent doing a task runs from first touch to handoff. Its only worked example is uninterrupted. It offers some useful time-accounting content, but its central rule and example do not support the interruption distinction. S1 can locate a connected explanation–example repair even if a prepared reader independently returns all correct quantities.
A revised explanation, M1, distinguishes active intervals from start-to-handoff turnaround, separates the columns, gives the interrupted report result, and states how to sum person-time across people. This repairs the named subject relation. To become an adequate contrast for all of S1, the material-and-support arrangement must also supply the concurrent example, a criterion that accepts valid equivalents, and the specified reader/feedback evidence. “Better explanation” alone is not a complete six-coordinate result.
An adequate constructed contrast combines M1 with the concurrent worked comparison, the S1 criteria, and an available teacher question and retry. It shows what adequate content and support would contain. Until an appropriate reader actually uses that arrangement, explanatory and feedback adequacy remain evidence requirements, not observed successes.
The outside-use contrast is “this reader will retain the distinction independently next month.” It concerns a human retention claim. S1 returns outside use and points to HCD.13; it does not award the handout 0.
The practical change is visible before collecting new learner data: M0 can no longer pass on heading coverage and expert accuracy alone; the repaired material cannot acquire a learning claim merely by containing the right definitions; and the remaining observation is specific enough to undertake.