Reliability R in the F–G–R triad
About this pattern
This is a generated FPF pattern page projected from the published FPF source. It is canonical FPF content for this ID; it is not a FPF Reference product feature page.
How to use this pattern
Read the ID, status, type, and normativity first. Use the content for exact wording, the relations for adjacent concepts, and citations to keep active work grounded without pasting the whole specification.
Reliability (R) is a conservative, evidence-bound warrant signal for a typed claim under an explicit claim scope (G). When reuse changes scope, kind, reference plane, notation, source-local meaning, model-use basis, or evidence basis, name the actual relation or operation and route only its declared congruence loss to R.
Type: Architectural (A) Status: Stable
KD‑CAL asks a simple operational question: “Where can I safely use this claim?” FPF answers with a minimal “epistemic location” built from three coordinates. Any relations traversed by a justification path are named separately:
Keywords
- Reliability (R)
- warrant
- evidence-bound
- F-G-R
- ClaimScope (G)
- direct relation
- Congruence Level (CL / CL^k / CL^plane)
- weakest-link
- pathwise justification (PathId)
- TA/VA/LA lanes
- no implicit averaging.
Relations
C.2:4.1Content
Problem frame
KD‑CAL asks a simple operational question: “Where can I safely use this claim?” FPF answers with a minimal “epistemic location” built from three coordinates. Any relations traversed by a justification path are named separately:
-
F (Formality) describes how the claim is expressed and how strongly it supports verification workflows (C.2.3).
-
G (Claim scope) describes where the claim is asserted to apply as a set-like object (A.2.6).
-
R (Reliability) describes how strongly the claim is warranted by linked evidence under that scope.
-
CL / CL^k / CL^plane (Congruence Levels) describe fit or loss for the relation families that define them—for example, a semantic relation, kind relation, or reference-plane relation (B.3, C.3, F.9). A CL value belongs to the declared relation or traversal used by the path, not to the claim as a fourth coordinate. Shared wording about a "context" creates no relation and no loss value. In practice, the triad is frequently used before it is made explicit:
-
Authors implicitly “average” disparate evidence and report a single confidence.
-
Teams treat higher formality (F) as if it automatically implies higher warrant (R).
-
Scope growth is smuggled in through phrasing instead of explicit scope operators (A.2.6).
-
A claim or its evidence is reused after a change of scope, kind, plane, notation, source-local meaning, model-use basis, or evidence basis without naming the actual relation and routing its declared loss into R.
This pattern makes R explicit in KD‑CAL and fixes the triad discipline required by Kind‑CAL (C.3) and the Trust & Assurance calculus (B.3).
Problem
FPF needs a reliability coordinate that is:
- Auditable. A reader can trace R to concrete evidence and see how reuse penalties were applied.
- Composable. R can be propagated through claim graphs conservatively, without illegal scale arithmetic.
- Orthogonal. R is not conflated with F (expression) or G (scope).
- Relation-aware. Any loss declared by an actual scope-translation, kind, plane, notation, source-local, model-use, or evidence-reuse relation is explicit and affects R only.
- Minimal. The solution does not introduce new core types or new face-kinds.
Forces
Solution
Canonical triad relation
Definition DEF‑C2.2‑1 (Epistemic location).
An epistemic location for a claim c is the tuple:
Loc(c) = ⟨F(c), G(c), R_eff(c)⟩
where:
F(c)is Formality (C.2.3), treated as an ordinal.G(c)is Claim scope (A.2.6), treated as a set-like scope object.R_eff(c)is Effective reliability forc, treated as a ratio-scale scalar in[0,1](or an ordinal proxy at [M‑0/M‑1]; see §4.5.A).R_effis computed pathwise (DEF‑C2.2‑3): when more than one admissible justification path exists, publish multiple path records (PathId rows) and cite which PathId(s) a guard/decision consumed (see §4.8.A / G.6). Any collapse to a single scalar is an explicitly declared Γ‑policy (no implicit averaging).
A location always concerns one exact claim. G carries its U.ClaimScope; any stance, reference plane, effective scheme, model-use basis, working situation, evidence basis, or validity window is stated separately when it changes interpretation or use:
- No generic
Kor Context value is part of epistemic-location identity; the exact subject-specific values above remain independently governed. S ∈ {design, run}is the claim’s stance carrier (no DesignRunTag chimeras).ReferencePlaneis declared where applicable; plane crossings applyCL^planeand penalize R only.- When the claim is published on the Working‑Model surface, the author also declares
validationMode ∈ {postulate, inferential, axiomatic}(E.14 / B.3).
Mode-to-lane hint (informative). validationMode sets the default expectation for which assurance lane carries the initial support load (B.3.3 or B.3.5).
It does not add a new characteristic and does not change the meaning of R:
axiomatic→ VA-dominant (constructive grounding or proof carriers); ifReferencePlane=world, LA may still be required.inferential→ VA+TA-dominant (reasoned chain + typing/alignment assurance); LA is optional and scope-bound.postulate→ LA-dominant (empirical validation with freshness/decay); VA is optional. In all modes, R remains warrant, not ontological truth; “proof ⇒ R=1 in the world” is a category error.
Profile note (informative; fold compatibility). Some profiles treat empirical R as N/A for strictly axiomatic lines and use a tagged proxy R_proxy := F (line=formal) for folding, as an explicit proxy rather than an implicit “F⇒R” rule (B.1.3).
⟨F,G,R⟩ is an assurance tuple, not a U.CharacteristicSpace; do not draw “trajectories” in ⟨F,G,R⟩.
What Reliability R means in KD‑CAL
Definition DEF‑C2.2‑2 (Reliability as warrant).
R is a conservative, evidence-bound indicator of how strongly the claim "holds as stated" under its declared U.ClaimScope and the separately named evidence and use conditions. It is interpreted as warrant strength, not as truth.
Prophylactic clarification.
- A higher
Rmeans “the evidence and its relevance supports relying on this claim under this scope.” - A higher
Fmeans “the claim’s form is amenable to higher-formality checking and wider reuse,” but does not itself imply the claim is warranted. - A larger
Gmeans “the claim applies to more cases,” but does not itself imply the claim is warranted in those cases.
Pathwise weakest-link propagation (series vs parallel)
KD‑CAL’s default Γ‑fold is weakest‑link on the entailment spine (the premises/lemmas actually needed), computed per justification path. It is conservative, monotone, and auditable.
Definition DEF‑C2.2‑3 (Pathwise weakest-link fold).
Let P be a justification path for claim c. Let SpineClaims(P) be the required supports on the entailment spine, and let SpineRelations(P) be the exact scope, kind, plane, notation, source-local, model-use, or evidence-reuse relations actually traversed on that spine.
Define the raw warrant of the path as:
R_raw(P) = min_{i ∈ SpineClaims(P)} R_eff(i)
and compute the effective warrant of the path by applying congruence penalties (see §4.5 for policy shape):
R_eff(P) = Π(R_raw(P); Φ(CL_min(P)), Ψ(CL^k_min(P)), Φ_plane(CL^plane_min(P)))
Spine discipline. The min is taken over the entailment spine only (no satellites, no “nice-to-have” citations).
This matches the KD‑CAL propagation rule (C.2:4.3) and the Trust & Assurance skeleton (B.3): weakest-link on the spine, penalize only by the worst (lowest) congruence encountered on the path (no averaging).
Parallel support (optional, declared).
If the same claim c has multiple independent justification paths {P_j} (OR‑style support), the default is:
R_eff(c) = max_j R_eff(P_j)
Independence is recorded as an explicit note (e.g., separate rigs/datasets/proof lines), per CC‑C.2.2‑10 and the KD‑CAL composition rule (C.2:4.3).
If the “multiple paths” actually cover different scope slices, do not use max to hide weaker slices; instead publish distinct G_path (SpanUnion‑style coverage) and keep per‑path R_eff traceable (A.2.6 / C.2:4.3).
Conflict detection (no averaging).
If the evidence graph supports both p and ¬p with overlapping scope, do not average. Separate the claims by the exact source, scheme, scope, model use, situation, or evidence basis that distinguishes them, or mark the claim provisional with explicit conflict edges until resolved.
Relation-specific congruence penalties route to R only
A reused claim may traverse more than one independently governed relation. Before calculating R_eff, state what actually changed and use the rule for that change. A.2.6 owns claim-scope operations; C.3/C.3.3 owns kind relations; F.9 owns a semantic Bridge between exact local-sense cells; notation, reference-plane, model-use, and evidence-reuse relations keep their own definitions. None is a universal crossing relation.
Invariant INV-C2.2-1 (R-only penalty routing). For each traversed relation r whose rule declares a congruence loss:
F_out = F_in
G_out = translate(r, G_in) only when r is an applicable A.2.6 scope translation; otherwise G_out = G_in
R_out ≤ R_in, with the exact penalty determined by r and the cited policy
A scope translation may narrow or re-express G; it never widens the claim silently. A change in formality is a new episteme or explicit ΔF move, not a transport penalty. A semantic Bridge changes neither kind nor scope by itself. A kind or plane relation supplies no semantic correspondence unless that separate relation also obtains. Evidence reuse changes warrant only through its own evidence-use or reliance claim.
There is no implicit crossing. If a reuse depends on a changed value and its required relation or operation is absent, unresolved, or outside its applicability, the reuse is non-conformant. This keeps guard macros simple: each path records the relations it actually traverses and routes their declared losses to R, while every other coordinate changes only under its own rule.
Worked micro-example: scope revision and evidence reuse
A materials-lab claim says:
c_lab:"Adhesive X retains ≥85% tensile strength on Al6061 for 2 h at 120–150 °C."
Its declared scope is G_lab := {substrate=Al6061, temp∈[120,150]°C, dwell≤2h, evidenceWindow=1y, rig=Calib-v3}. A plant engineer proposes a narrower claim for Plant B. Two different moves are required.
- State the plant claim and its scope. Under A.2.6 the engineer explicitly narrows the temperature interval to
[122,148]°Cbecause the plant calibration rule reports a ±2 °C bias. This changesG; it is not an F.9 semantic Bridge and is not inferred from the words "lab" and "plant". - Judge reuse of the lab evidence. The exact A.10 or B.3 evidence-use and reliance claim names the lab evidence, plant claim, calibration edition, validity window, and intended use. If that relation's declared fit is
CL=2under policyΦ_v1, computeR_eff := max(0, R_lab − Φ_v1(2)). The penalty reduces warrant; it does not perform the scope edit.
If lab and plant use distinct local meanings for a material term, F.9 separately tests a Bridge between their exact F.17 cells. Its semantic loss is not the calibration correction or the evidence-reuse result. A further safety narrowing to [125,145]°C is another explicit A.2.6 ΔG− decision.
The example therefore preserves one simple rule: name each changed value and relation once, change G only through the scope rule, and reduce R only through the loss rule that actually applies.
Effective reliability under transport (policy-defined, monotone, bounded)
When a claim is reused through declared relations, R_eff is computed by applying the penalties those relations assign to their congruence levels.
Definition DEF‑C2.2‑4 (Effective reliability under transport). Let:
CLbe the congruence level declared by the applicable scope, semantic, notation, model-use, or evidence-reuse relation (B.3 and its direct subject pattern).CL^kbe the congruence level of an applicable kind relation (C.3/C.3.3).CL^planebe the congruence level of an applicable reference-plane relation (B.3 / plane patterns).
Let Φ, Ψ, and Φ_plane be policy-defined, monotone, bounded, table-backed penalty policies applied on the relevant edges:
Φ(CL)— penalty declared for the applicable scope, semantic, notation, model-use, or evidence-reuse relation.Ψ(CL^k)— penalty declared for an applicable kind relation.Φ_plane(CL^plane)— plane-crossing penalty whenReferencePlanediffers.
Important (direction of monotonicity). Congruence ladders are “polarity up” (higher CL = better fit). Per CC‑G0‑Φ and the Trust & Assurance skeleton, penalty tables are monotone decreasing in their CL ladders (if CL1 < CL2 then Φ(CL1) ≥ Φ(CL2), analogously for Ψ and Φ_plane) and bounded so that R_eff remains within [0,1] after clipping. Penalty magnitudes are not required to lie in [0,1] (tables may exceed 1 to force R_eff → 0 under the subtractive default); what matters is monotonicity, boundedness, and published policy identifiers.
Define:
R_eff(P) = clip_0^1( Π(R_raw(P); Φ(CL_min(P)), Ψ(CL^k_min(P)), Φ_plane(CL^plane_min(P))) )
where each *_min(P) is the lowest congruence level encountered on the entailment spine of P for that dimension (a bottleneck; no averages), and clip_0^1(x) truncates to [0,1].
Default (safe) instantiation (subtractive). When policies are expressed as subtractive penalties, a safe default is:
R_eff(P) = max(0, R_raw(P) − Φ(CL_min(P)) − Ψ(CL^k_min(P)) − Φ_plane(CL^plane_min(P)) )
This generalises the B.3 skeleton to multiple congruence ladders (scope vs kind vs plane) without introducing new penalty characteristics. If a dimension is not present on the path, its penalty term is treated as neutral (0 in the subtractive default).
Provisional marking.
Default admissibility thresholds for reuse are set by the relevant relation-calibration profile (e.g., G.7). Typically, CL=1 requires an explicit waiver to proceed and CL=0 is inadmissible; this pattern only specifies that such thresholds gate reuse before any numeric penalty is meaningful.
Math-by-level gating (B.1.3:4.3)
- [M‑0/M‑1] allow ordinal comparisons only (no arithmetic on
R_eff); Φ/Ψ/Φ_plane may be qualitative (“low/med/high”). Publish evidence links + lane tags. - [M‑2/L1] numeric
R_effrequires referencing numeric, table-backed policy identifiers for Φ/Ψ/Φ_plane (and Π if not default), plus reproducibility tags for empirical legs; otherwise treat the claim as [M‑1] semantics.
Evidence lanes are not new characteristics
KD‑CAL does not add new global coordinates beyond F–G–R. Instead, it requires that reliability be explainable via assurance lanes (B.3.3):
- TA (Typing assurance): semantic/type alignment sufficient for transport and composition.
- VA (Verification assurance): logical/algorithmic checking, proof, model checking, static guarantees.
- LA (Validation assurance): empirical adequacy under declared conditions, tests, benchmarks, telemetry.
Lane reporting is how KD-CAL supports the common research distinction between logical soundness and empirical adequacy without introducing new global characteristics. Lanes remain separable in SCR/Notes; they are not averaged into a “single tradition score”.
Scope operations are kind-safe (and use the ClaimScope algebra)
Reliability is meaningless if scope operations are applied to ill-typed entities.
Well-formedness constraint WFC‑C2.2‑1 (Type before scope).
Let G1 and G2 be claim scopes for claims about entities of kinds K1 and K2. A scope operation that combines them—such as G1 ∩ G2 for serial intersection or SpanUnion({G_i}) for parallel coverage—is defined only if:
K1 = K2; or- an exact C.3/C.3.3 kind relation or cast makes the operation well typed for these participants and this direction.
An A.2.6 scope translation changes G only under its own rule. A kind relation does not translate scope. If distinct source-local meanings also matter, an actual F.9 Bridge and its bounded-use claim are separate; neither repairs an ill-typed scope operation.
This constraint prevents “type-by-scope” anti-patterns where scope manipulation is used to hide type mismatch.
Minimal authoring recipe
A minimal, conforming KD‑CAL authoring flow for reliability is:
- Fix the typed claim. State the claim as a typed proposition about a EntityOfConcern (Kind‑CAL, C.3).
- Declare claim scope. Write
Gexplicitly using A.2.6 operators; avoid scope-by-wording. - Declare interpretation conditions. State design or run stance,
ReferencePlane, effective scheme, model-use basis, working situation, andvalidationMode ∈ {postulate, inferential, axiomatic}only where each changes this claim or its use.Galready carries claim scope; do not add a generic Context identifier. - Bind evidence. Attach evidence stubs and lane tags (TA/VA/LA) and validity windows / decay policy where applicable (B.3.3, B.3.4).
- Choose Γ-mode. Declare whether the support is series (required) or parallel (independent lines to the same claim).
- Compute R_raw. Use the weakest-link fold on the entailment spine; for parallel support, use
maxonly with an explicit independence note. - Name actual relations on reuse. Use A.2.6 for an applicable scope translation, C.3/C.3.3 for a kind relation, F.9 for a semantic relation between exact local-sense cells, and the direct pattern for notation, plane, model-use, or evidence reuse. Record the fit or loss declared by each traversed relation. If a required relation is absent or unresolved, stop that reuse; a generic cross-context Bridge cannot substitute for it.
- Compute R_eff. Apply the declared penalty policies into
R(never intoForG), and publish⟨F,G,R_eff⟩with traceable references and policy identifiers.
A reliable claim is not a loud claim; it is a claim that can be carried.
Authoring template: Path summary row (copy/paste)
When publishing R_eff for a claim, authors SHOULD include a compact, claim-local path summary. This is intentionally shaped so it can be turned into tooling later (EvidenceGraph/PathId in G.6) without introducing new Core types or face-kinds.
Notes:
CL_*_minvalues are bottlenecks on the relevant path/dimension (no averaging).valid_untilis the earliest expiry across empirical legs (or—/ “fenced to TheoryVersion” for non-decaying proof legs).- If you publish multiple admissible paths, include multiple rows and cite which PathId(s) your decision/guard consumed.
Archetypal Grounding
Informative; non-binding.
System illustration
System. A brake controller S has a claim:
c1:“For road friction μ ∈ [0.2, 0.9] and vehicle mass m ∈ [900, 2200] kg, wheel slip stays in [0.05, 0.25] under ABS control.”
-
F(c1)=F5because the controller and constraints are expressed as a machine-checkable model plus executable test harness (C.2.3). -
G(c1)is the declared operating envelope (A.2.6) as a product set in(μ, m, speed, tire)space. -
Evidence:
- VA: model-checking of a simplified plant/controller model (strong, but only for the simplified plant).
- LA: HIL simulation + track tests under sampled conditions with recorded telemetry windows (freshness required).
- TA: typed alignment between “μ” in simulations, “μ” in the estimation pipeline, and “μ” inferred from real-world sensors.
If track telemetry is used as evidence for the road claim, establish the exact A.10 or B.3 evidence-use and reliance claim, including the road claim, telemetry edition, operating scope, validity window, and intended use. Apply only the fit or loss declared for that evidence reuse; G(c1) changes only through a separate A.2.6 scope revision.
Episteme illustration
Episteme. A paper asserts two claims about an algorithm A:
c2:“A terminates for all inputs in domain D.” (axiomatic / proof-carrying)c3:“A achieves ≥ 0.92 F1 on dataset family F under deployment preprocessing P.” (empirical)
c2 can achieve high VA with a proof carrier; its LA lane may be N/A, but its TA lane remains relevant because the intended meaning of “domain D” must align with the implementation’s input model.
c3 requires LA evidence and a freshness or shift policy because dataset and preprocessing drift can change both scope and warrant. For production use, state the exact dataset/preprocessing relation and the A.10 or B.3 evidence-reuse claim, then apply its declared loss to R_eff; change G separately if the production claim has another scope.
Bias-Annotation
Informative; non-binding.
Lenses tested: Gov, Arch, Onto/Epist, Prag, Did. Scope: Universal.
- Onto/Epist bias: High formality is often mistaken for high warrant (“proof therefore true in the world”). This pattern mitigates by forcing LA/TA visibility and by routing transport loss into R rather than mutating the claim.
- Prag bias: Teams may Goodhart R by narrowing scope or selecting easy tests. This pattern mitigates by requiring explicit scope declaration and by making scope changes first-class (A.2.6).
- Gov bias: Overconfident reuse after a changed scope, scheme, model use, evidence basis, kind, or plane is a recurring failure. This pattern requires the actual relation and its declared loss instead of one generic crossing label.
- Did bias: A single scalar is seductive; it hides what kind of warrant exists. Lane reporting keeps the scalar honest.
Conformance Checklist
Normative.
Common Anti-Patterns and How to Avoid Them
Informative; non-binding.
Consequences
Informative; non-binding.
Rationale
A triad only works if each coordinate has a single job.
- G carries entitlement. It states where the claim is asserted to apply. If G is implicit, teams argue about “what was meant” instead of updating scope.
- F carries checkability. It states how much the claim’s form supports mechanised scrutiny and reuse. If F is conflated with R, formalisation becomes a rhetorical weapon.
- R carries warrant. It states how much evidence supports relying on the claim under G. If R is not conservative, evidence with a low
Rcoordinate can be laundered into high confidence.
Routing a traversed relation's declared congruence loss into R only prevents a subtle failure: a change of scope, kind, plane, notation, source-local meaning, model-use basis, or evidence basis cannot silently rewrite the claim or carry its old warrant forward.
Weakest-link propagation is chosen because it is the simplest rule that is monotone, conservative, and auditable. When better combination rules exist, they can be introduced as explicit Γ‑policies, but the default must be safe.
SoTA-Echoing
Normative.
SoTA pack binding note. If a G.2 SoTA Synthesis Pack has sources that bear on reliability under the exact changed claim scope, kind, reference plane, notation, source-local meaning, model use, or evidence basis in this case, cite the relevant ClaimSheet IDs and CorpusLedger entries. Cite a BridgeMatrix row only when the current path actually uses an F.9 cross-local semantic Bridge represented by that row. Otherwise record SoTA-Pack: TBD/none and treat this section as the seed; neither a generic Context nor a generic transport package is required.
Relations
Builds on: C.2 (KD-CAL overview), A.2.6 (claim scope and scope revision), C.2.3 (Formality F), B.3 and B.3.3/B.3.4 (assurance, evidence lanes, and refresh), B.1.3 (Γ-fold patterns), C.3.3 (cross-kind use), G.6 (EvidenceGraph PathId discipline), C.29/A.6.3.RT (notation and representation relations), A.1.1 (selected model-use structure), and A.10/B.3 for exact evidence-use and reliance relations. F.9 is used only when an obtaining relation between distinct local meanings, reference schemes, or reference planes is part of the path.
Coordinates with: C.16 for measurement claims, E.14 for working-model assertions, F.17 for optional local-meaning addresses, and E.18/E.17/A.21 when their own transfer, publication, or gate objects are current. G.2 supplies relevant source-pack entries; G.7 remains the conditional calibration path for its declared cross-Tradition/F.9 Bridge use, not a universal calibration owner.
Used by: C.3.3 for cross-kind reuse discipline, guard macro bundles in C.3.A and C.21, and acceptance or gating logic that consumes R_eff while preserving F and G.
Clarifies: the KD-CAL meaning of reliability implicit in C.2:4.1 and the relation-specific reuse claims referenced across B.3 and C.3; it does not create a universal transport relation.
C.2.2:End
Last Updated: 2026-08-30 — upstream FPF commit e400eab3 (github.com/ailev/FPF)