{
  "format": "vercy-model-allocation-fixtures/v1",
  "proposedName": "Metric Definition",
  "version": "0.1.0-candidate.3",
  "cases": [
    {
      "id": "method-and-population-change",
      "kind": "positive",
      "input": "Headcount under method A and population P1 changes to headcount under method B and population P2 while phenomenon, quantity kind and statistical unit type remain unchanged.",
      "expect": "Metric identity remains; a new immutable DefinitionVersion is created and defaults to non-comparable until an explicit verdict is published."
    },
    {
      "id": "missing-not-zero",
      "kind": "negative",
      "input": "One reporting period has no observation.",
      "expect": "The period remains missing or unknown and is never substituted with zero."
    },
    {
      "id": "recalculation",
      "kind": "positive",
      "input": "Historical source data is recalculated under a successor definition.",
      "expect": "New observations pin the successor version; old observations remain unchanged."
    },
    {
      "id": "invalid-aggregation",
      "kind": "negative",
      "input": "A semi-additive metric is summed over an unsupported time dimension.",
      "expect": "Aggregation fails closed under the dimension rule."
    },
    {
      "id": "headcount-plus-fte",
      "kind": "negative",
      "input": "Person headcount observations are summed with FTE observations.",
      "expect": "Aggregation is refused because quantity kind, statistical unit and definition version are not commensurable."
    },
    {
      "id": "undeclared-additivity",
      "kind": "negative",
      "input": "A metric is aggregated across a dimension with no additivity declaration.",
      "expect": "Aggregation is refused because undeclared is not additive."
    },
    {
      "id": "explicit-restatement",
      "kind": "positive",
      "input": "Two versions differ but an approved restatement method and evidence exist.",
      "expect": "Comparability is comparable-with-restatement and references the method and evidence."
    },
    {
      "id": "restatement-preserves-vintage",
      "kind": "positive",
      "input": "A published mapping restates four historical periods under a successor definition.",
      "expect": "Four new observation vintages are created and every prior observation remains resolvable."
    },
    {
      "id": "target-version-pin",
      "kind": "negative",
      "input": "A target bound to definition V1 is evaluated silently with V2 observations.",
      "expect": "Evaluation is refused until the target is explicitly rebound or a declared restatement is applied."
    },
    {
      "id": "quantity-kind-reidentification",
      "kind": "negative",
      "input": "A headcount-person Metric is changed to an FTE Metric.",
      "expect": "A new Metric identity is required; correspondence may be recorded but DefinitionVersion continuity is rejected."
    },
    {
      "id": "restatement-missing-evidence",
      "kind": "negative",
      "input": "A comparability declaration says comparable-with-restatement but has no pinned method or evidence.",
      "expect": "The declaration is rejected."
    },
    {
      "id": "equal-authority-conflict",
      "kind": "negative",
      "input": "Two active definition sources claim equal authority for the same Metric and effective scope.",
      "expect": "Automatic merge and winner selection are refused; the conflict is surfaced."
    },
    {
      "id": "facet-cannot-widen",
      "kind": "negative",
      "input": "Metric-level verdict is non-comparable while one facet claims comparable.",
      "expect": "The facet may not widen the aggregate verdict and comparison is refused."
    },
    {
      "id": "withdrawn-remains-resolvable",
      "kind": "positive",
      "input": "A superseded DefinitionVersion is later withdrawn and tombstoned.",
      "expect": "Its identifier, digest, predecessor and provenance remain resolvable."
    }
  ]
}