feat(psychometric): recover Driver p.16 DRIFTstd after positive asymDIFFUSION - #190
Conversation
…IFFUSION
Driver, Oud, and Voelkle (2017, p. 16; Eq. 1; footnote 4; §7.1) print
standardised matrices with the suffix std when appropriate. Footnote 4
standardises DRIFT using only the relevant variance, not the total.
That variance is within-subject asymDIFFUSION. Form strictly positive
-q/(2a) first. In the scalar stationary case the SD ratio is 1, so the
standardised auto-effect equals a numerically; those remain distinct
named quantities. Unstandardised a is defined for growing a ≥ 0 and
for zero diffusion; standardised DRIFT is not. Discrete e^{a Δt} is
not DRIFTstd. a p / (trait + p + added) uses TRAITVAR and is not
DRIFTstd. Still not a Kalman filter, not a matrix expm, not ESEM
estimation, not DSEM, and not ctsem estimation.
|
Important Review skippedDraft detected. Please check the settings in the CodeRabbit UI or the ⚙️ Run configurationConfiguration used: Organization UI Review profile: CHILL Plan: Pro Plus Run ID: You can disable this status message by setting the Use the checkbox below for a quick retry:
Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out. Comment |
|
Folded into the consolidation vehicle #231; this draft stays open until the vehicle merges, then closes as superseded-by-consolidation. |
|
Superseded by consolidation: this slice's Driver et al. (2017) standardization recovery landed on protected main through the integration vehicles (#231/#232), and its contract coverage is carried by the reconciled suites (multilevel_event_time_recovery_contract, rubin_and_mean_gate_contract) with test-signature repair tracked in #234. The stacked-draft form is retired to keep the delivery queue at review-ready work only; no capability is lost — the exact-head provenance remains in the vehicle PR descriptions and CHANGELOG. |
1 participant
Stacked on #189 (
0836c35) / #188 (444304d) / #187 (6afd048) / #185 (69ffec6) / #184 (6b93147) / #183 (c10097be) / #182 (2d4d6bf) / #181 (542806b) / #49 (6f95142). ADR 0005 executable slice stays insidepsychometric_core. This is not a second invariance crate and does not recreate #78 or #80.psychometric_corerecovers the Driver, Oud, and Voelkle (2017, p. 16DRIFTstd; Eq. 1, p. 4; footnote 4; §7.1, pp. 18–19; JSS PDF re-opened 2026-08-23T13:28Z from https://www.jstatsoft.org/index.php/jss/article/download/v077i05/1104) scalar standardised continuousDRIFT. Page 16 prints continuous-time parameters (e.g.,DRIFT) and, when appropriate, standardised matrices with the suffixstd. Footnote 4: standardisations use only the relevant variance, not the total. ForDRIFTthat relevant variance is within-subjectasymDIFFUSION-q / (2 a), becauseDRIFTis intended to represent individual, or average individual, temporal dynamics.Form strictly positive
asymDIFFUSIONfirst. In the scalar stationary case the within-subject SD ratio is 1, so the standardised auto-effect equals the unstandardised log-rate numerically; those remain distinct named quantities.ais defined for growinga ≥ 0and for zero diffusion; standardisedDRIFTis not.asymDIFFUSIONhas no positive SD and fails closed (StandardisedContinuousDriftRequiresPositiveWithinSubjectVariance).a ≥ 0cannot form finiteasymDIFFUSIONand fails closed (StationaryVarianceRequiresStableDrift).e^{a Δt}depends on the event interval and is notDRIFTstd.a p / (trait + p + added)uses the total, notasymDIFFUSION, and is notDRIFTstdwhenTRAITVARis nonzero.TRAITVARis not the footnote 4 standardisation variance.Still not a Kalman filter, not a matrix
expm, not ESEM estimation, not DSEM, and not ctsem estimation. Meredith (1993) remains unread (Unpaywall 2026-08-23T13:19Z:is_oa: false; title Measurement Invariance, Factor Analysis and Factorial Invariance). Mislevy (1991, Psychometrika, 56, 177–196) remains unread (Unpaywall 2026-08-23T13:19Z:is_oa: false; title Randomization-Based Inference about Latent Variables from Complex Samples).Do not merge, self-approve, or request Copilot.