PR-CS-8: Association strength (ΔR²) — per-scope effect-size guide for the Analyze Wall

docs/decision-log.md

@@ -28,6 +28,10 @@ When in doubt: capture, don't invent. Record the decision; link to its source ar
 
 Decisions we keep relitigating. Each entry: short statement, rationale, closing artifact, date pinned.
 
+- **2026-06-03 — CS-8 refines LOCKED #2: the factor-evaluation surface adds per-factor ΔR² ("association strength"), still no Cp/BIC.** `code`: `feat/cs-8-association-strength` (PR pending); `spec`: [`2026-05-31-factors-evaluation-design.md`](superpowers/specs/2026-05-31-factors-evaluation-design.md) §2; sub-plan [`2026-06-02-cs-8-association-strength.md`](superpowers/plans/2026-06-02-cs-8-association-strength.md).
+
+  LOCKED #2 ("surface metrics = adjusted R² + per-factor p ONLY") is **refined, not reopened**: the `ModelBuilderBand` now also surfaces each factor's **semipartial R²** (`ΔR² = R²(kept) − R²(kept∖f)` for a kept factor; gain-on-add for a candidate) as the **effect-size magnitude paired with the existing partial p** — the same numerator the nested-F partial p is built on (`perFactorDeltaR2`, an O(1) read off the enumerated subset index, no new regression). It is raw R² (so ≥0, on the share-of-the-total-spread scale) and **explicitly non-summing** (honors ADR-073 — contribution, never a forced variance decomposition; correlated factors' shared variance is attributed to no single factor). Framed in-UI as an association clue, **never a cause verdict** (a `model-not-a-verdict` line + caption). Cp/BIC remain OFF the surface — ΔR² is an effect size, not a model-selection criterion, so the Cp/BIC bar is untouched. Rejected: ΔR²adj (can go negative), partial R² (off the total-variance scale), relabel-only (loses the magnitude).
+
 - **2026-06-02 — Documentation alignment completes before further product refactoring.** `new spec`: [`docs/superpowers/specs/2026-06-02-documentation-alignment-design.md`](superpowers/specs/2026-06-02-documentation-alignment-design.md) (draft).
 
   A grounded multi-agent audit (against commit `fff607f2`) found the shipped V1 surface is **~1-in-6 documented** — 57 capabilities: 10 current / 7 stale / 12 partial / 28 missing. Root cause is the **systematically-skipped SDD Apply phase**: specs ship as `delivered` (code lands) while their `implements:` target docs are never written (`2026-05-29-investigation-surface`, `2026-05-31-factors-evaluation`, `2026-05-26-canvas-connection-journey`, `2026-05-28-state-edit-mode` all show this).

docs/superpowers/specs/2026-05-31-factors-evaluation-design.md

@@ -42,7 +42,7 @@ The Wall ships with a live-derived status, comments, ActionItem tasks, the Measu
 ### Locked design calls (product owner, 2026-05-31)
 
 1. **"Simplest adequate" default** = the fewest factors **within 1 point of the max adjusted R²** where each kept factor's **p < .15**; the analyst adjusts from there. (ADR-088 amendment + a tunable.)
-2. **Surface metrics = adjusted R² + per-factor p ONLY.** No Mallows Cp / BIC on the surface (Cp may be an _internal_ picker metric only). Keep it simple and meaningful.
+2. **Surface metrics = adjusted R² + per-factor p + per-factor ΔR² ("association strength") ONLY.** No Mallows Cp / BIC on the surface (Cp may be an _internal_ picker metric only). Keep it simple and meaningful. _(Refined CS-8, 2026-06-03: ΔR² = each factor's **semipartial R²** — `R²(kept) − R²(kept∖f)` for a kept factor, gain-on-add for a candidate — the effect-size magnitude paired with the existing partial p, on the same numerator. Raw R² so ≥0, on the share-of-the-spread scale, and **non-summing per ADR-073**. It is an effect size, not a model-selection criterion, so it does not reopen the Cp/BIC question.)_
 3. **Evaluate is one-tap, never auto-run** (avoids implying a post-selection p is a clean pre-planned test).
 4. **A manual model override is VIEW-STATE while exploring; the _concluded_ model is saved via capture-as-Finding** (the Finding snapshots the factors — `FindingProjectionModelContext` already carries `rSquaredAdj`/`scopeLabel`/`linkedFactor`). No stored selection field; no Finding-per-toggle.
 5. **Terminology:** top status label is **"Supported"** (shipped #259); "Counts against" stays loud.

packages/core/src/i18n/messages/ar.ts

@@ -949,6 +949,12 @@ export const ar: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',

packages/core/src/i18n/messages/bg.ts

@@ -958,6 +958,12 @@ export const bg: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',

packages/core/src/i18n/messages/cs.ts

@@ -871,6 +871,12 @@ export const cs: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',

packages/core/src/i18n/messages/da.ts

@@ -922,6 +922,12 @@ export const da: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',

packages/core/src/i18n/messages/de.ts

@@ -961,6 +961,12 @@ export const de: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',

packages/core/src/i18n/messages/el.ts

@@ -961,6 +961,12 @@ export const el: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',

packages/core/src/i18n/messages/en.ts

@@ -970,6 +970,12 @@ export const en: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',

packages/core/src/i18n/messages/es.ts

@@ -963,6 +963,12 @@ export const es: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',

packages/core/src/i18n/messages/fi.ts

@@ -959,6 +959,12 @@ export const fi: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',

packages/core/src/i18n/messages/fr.ts

@@ -967,6 +967,12 @@ export const fr: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',

packages/core/src/i18n/messages/he.ts

@@ -947,6 +947,12 @@ export const he: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',

packages/core/src/i18n/messages/hi.ts

@@ -959,6 +959,12 @@ export const hi: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',

packages/core/src/i18n/messages/hr.ts

@@ -954,6 +954,12 @@ export const hr: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',

packages/core/src/i18n/messages/hu.ts

@@ -875,6 +875,12 @@ export const hu: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',

packages/core/src/i18n/messages/id.ts

@@ -910,6 +910,12 @@ export const id: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',

packages/core/src/i18n/messages/it.ts

@@ -931,6 +931,12 @@ export const it: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',

packages/core/src/i18n/messages/ja.ts

@@ -920,6 +920,12 @@ export const ja: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',

packages/core/src/i18n/messages/ko.ts

@@ -920,6 +920,12 @@ export const ko: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',

packages/core/src/i18n/messages/ms.ts

@@ -959,6 +959,12 @@ export const ms: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',

packages/core/src/i18n/messages/nb.ts

@@ -872,6 +872,12 @@ export const nb: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',

packages/core/src/i18n/messages/nl.ts

@@ -930,6 +930,12 @@ export const nl: MessageCatalog = {
   'wall.model.vitalFewLine': 'vital-few line',
   'wall.model.rSquaredAdj': 'R²adj {value}',
   'wall.model.factorP': 'p {value}',
+  'wall.model.associationStrength': 'Association strength',
+  'wall.model.deltaR2': 'ΔR² {value}',
+  'wall.model.notAVerdict':
+    'Associated with the spread in this scope — a clue to investigate, not a verdict.',
+  'wall.model.deltaR2Caption':
+    'Each bar is a factor’s unique share of the spread; correlated factors overlap, so they need not sum to the model fit.',
   'wall.model.useSuggested': '↩ Use suggested model',
   'wall.model.addToModel': 'Add {factor} to the model',
   'wall.model.removeFromModel': 'Remove {factor} from the model',