feat(psychometric): recover 2017-era active asymptotes=TRUE TIPREDEFFECT rewrite on main

CHANGELOG.md

@@ -38,6 +38,7 @@ All notable changes to TEPP are documented here. The format follows Keep a Chang
 
 ## [Unreleased]
 
+- `psychometric_core` recovers the 2017-era active `asymptotes=TRUE` `TIPREDEFFECT` rewrite as `−a · B` on current main (Driver, Oud, & Voelkle, 2017, Table 2, p. 12; Eq. 1, p. 4; Eq. 3, p. 5; §7.2, pp. 20–21; p. 16; 2017-era ctsem `summary.ctsemFit.R`; JSS PDF re-opened 2026-08-31T05:20Z from https://www.jstatsoft.org/index.php/jss/article/download/v077i05/1104). cran/ctsem 2.5.0 `summary.ctsemFit.R` forms `if(asymptotes==TRUE) TIPREDEFFECT <- -DRIFT %*% mxobj$TIPREDEFFECT$values` when `n.TIpred > 0`. That rewrite is active and is in the `outlist`. Form `a` first, then negate, then multiply by `B`. When `asymptotes=TRUE` the stored `TIPREDEFFECT` is the asymptotic parameterization §7.2 names `asymTIPREDEFFECT` `-B / a`; multiplying by `-DRIFT` converts that stored value back to original `B`. The rewrite is the coefficient `B`, not `B z`. The companion active rewrite `CINT <- -DRIFT %*% CINT` uses the same operator on a different matrix and is not this coefficient map. A zero coefficient is exactly zero even if `a ≥ 0`. `a ≥ 0` with a nonzero coefficient fails closed. Numeric: `a = −0.5`, `B = 0.4` recovers 0.2, distinct from unstandardised `TIPREDEFFECT` (0.4), from unit `asymTIPREDEFFECT` `-B / a` (0.8), from `discreteTIPREDEFFECT` at `Δt = 1` (≈ 0.3148), and from Table 2 `CINT` when `κ = B`. Stored `-B / a = 0.8` recovers original `TIPREDEFFECT` 0.4. Unstandardised `TIPREDEFFECT` is not this rewrite. A non-event clock fails closed. Meredith (1993) remains unread (Unpaywall 2026-08-31T05:10Z: `is_oa: false`; Springer `content/pdf` is an HTML stub; escholarship hits are citations). Mislevy (1991, *Psychometrika, 56*, 177–196, DOI 10.1007/bf02294457) remains unread on the same terms. Still not a Kalman filter, not a matrix `expm`, not ESEM estimation, not DSEM, and not ctsem estimation.
 - Removed the repository-local hourly PR-maintenance caller now covered by the central required scheduler, retired stale workflow registrations, narrowed documentation triggers, keyed PR concurrency by fixed workflow name, repository, and pull-request number without cancelling non-PR runs, and combined line/branch coverage on one sequential runner while preserving both 100% gates and diagnostics.
 
 - `event_core` adds bounded Allen interval-consistency classification, atomic path-consistency closure, contradiction/resource refusals, and an explicit dependency-error fallback without claiming unrestricted global satisfiability.

crates/psychometric_core/src/error.rs

@@ -710,6 +710,29 @@ pub enum PsychometricError {
     /// `MANIFESTVARstd`. `λ² Var(η) + θ` is `Var(y)`, not the
     /// correlation form of `Θ`.
     ObservedVarianceIsNotStandardisedManifestVariance,
+
+    /// 2017-era active `if(asymptotes==TRUE) TIPREDEFFECT <- -DRIFT %*%
+    /// TIPREDEFFECT` was requested for a non-stable drift. That rewrite
+    /// is `−a · B` and converts the asymptotic-parameterization stored
+    /// `TIPREDEFFECT` back to original `B`. Lasting conversion requires
+    /// `a < 0`. A zero coefficient is exactly zero even if `a ≥ 0`.
+    AsymptotesTrueTimeIndependentEffectRequiresStableDrift,
+    /// Unstandardised `TIPREDEFFECT` `B` was treated as the 2017-era
+    /// active `asymptotes=TRUE` rewrite. `B` is not `−a · B` when
+    /// `a ≠ −1`.
+    UnstandardisedTimeIndependentCoefficientIsNotAsymptotesTrueTimeIndependentEffect,
+    /// Driver §7.2 `asymTIPREDEFFECT` `-B / a` was treated as the
+    /// 2017-era active `asymptotes=TRUE` `TIPREDEFFECT` rewrite. The
+    /// stored asymptotic coefficient is not `−a · B`.
+    AsymptoticTimeIndependentEffectIsNotAsymptotesTrueTimeIndependentEffect,
+    /// Driver `discreteTIPREDEFFECT` `A^{-1}[e^{A Δt} − I] B` was
+    /// treated as the 2017-era active `asymptotes=TRUE` `TIPREDEFFECT`
+    /// rewrite. A finite event interval is not `−a · B`.
+    DiscreteTimeIndependentEffectIsNotAsymptotesTrueTimeIndependentEffect,
+    /// Driver Table 2 `CINT` `κ` was treated as the 2017-era active
+    /// `asymptotes=TRUE` `TIPREDEFFECT` rewrite. The same operator
+    /// on a different named matrix is not this coefficient rewrite.
+    ContinuousInterceptIsNotAsymptotesTrueTimeIndependentEffect,
 }
 
 impl fmt::Display for PsychometricError {
@@ -1235,6 +1258,21 @@ impl fmt::Display for PsychometricError {
             Self::ObservedVarianceIsNotStandardisedManifestVariance => {
                 "observed-indicator variance is not standardised measurement-error variance"
             }
+            Self::AsymptotesTrueTimeIndependentEffectRequiresStableDrift => {
+                "asymptotes-true time-independent effect requires a stable negative drift"
+            }
+            Self::UnstandardisedTimeIndependentCoefficientIsNotAsymptotesTrueTimeIndependentEffect => {
+                "unstandardised time-independent coefficient is not asymptotes-true time-independent effect"
+            }
+            Self::AsymptoticTimeIndependentEffectIsNotAsymptotesTrueTimeIndependentEffect => {
+                "asymptotic time-independent effect is not asymptotes-true time-independent effect"
+            }
+            Self::DiscreteTimeIndependentEffectIsNotAsymptotesTrueTimeIndependentEffect => {
+                "discrete time-independent effect is not asymptotes-true time-independent effect"
+            }
+            Self::ContinuousInterceptIsNotAsymptotesTrueTimeIndependentEffect => {
+                "continuous intercept is not asymptotes-true time-independent effect"
+            }
         };
         formatter.write_str(message)
     }
@@ -2073,4 +2111,32 @@ mod tests {
             "measurement error is not standardised manifest-trait variance"
         );
     }
+
+    #[test]
+    fn asymptotes_true_time_independent_effect_boundary_messages_are_stable() {
+        assert_eq!(
+            PsychometricError::AsymptotesTrueTimeIndependentEffectRequiresStableDrift.to_string(),
+            "asymptotes-true time-independent effect requires a stable negative drift"
+        );
+        assert_eq!(
+            PsychometricError::UnstandardisedTimeIndependentCoefficientIsNotAsymptotesTrueTimeIndependentEffect
+                .to_string(),
+            "unstandardised time-independent coefficient is not asymptotes-true time-independent effect"
+        );
+        assert_eq!(
+            PsychometricError::AsymptoticTimeIndependentEffectIsNotAsymptotesTrueTimeIndependentEffect
+                .to_string(),
+            "asymptotic time-independent effect is not asymptotes-true time-independent effect"
+        );
+        assert_eq!(
+            PsychometricError::DiscreteTimeIndependentEffectIsNotAsymptotesTrueTimeIndependentEffect
+                .to_string(),
+            "discrete time-independent effect is not asymptotes-true time-independent effect"
+        );
+        assert_eq!(
+            PsychometricError::ContinuousInterceptIsNotAsymptotesTrueTimeIndependentEffect
+                .to_string(),
+            "continuous intercept is not asymptotes-true time-independent effect"
+        );
+    }
 }