Model discrepancy, calibration and predictive uncertainty
Research context
research method · conditional · As of 2026-10-10
A discrepancy term δ(x) represents inadequacy of the physical response model, distinct from repeatability noise and uncertain calibration parameters.
Key knowledge
A discrepancy term δ(x) represents inadequacy of the physical response model, distinct from repeatability noise and uncertain calibration parameters. If δ can freely mimic parameter changes, the two are confounded. Validate observables outside the fit with declared discrepancy structure, independent references and uncertainty; inflating residual variance alone need not protect predictions.
Values and equations
y(x)=f(x,θ)+δ(x)+ε(x)
- y,f,δ,ε
- Observed response, predicted response, discrepancy and noise; common output units
- x
- Controlled/input quantities with specified units
- θ
- Calibration/model parameters
Conditions and scope
- Model δ using physical bounds, structured stochastic assumptions or competing model sensitivity; state units, correlation length and priors.
- A small fitted residual cannot certify an extrapolated response. Separate numerical error, shared reference bias and model error in the budget.
Sources · 2
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
Evidence and review
Inspected §§8.5, 10.4–10.6, 11.4, 11.6–11.10, 12 and Annex B: shared effects, inverse calibration, time series and prior sensitivity; source check dated 2026-10-10. Scope is limited to the cited statements, equations and assumptions, not the whole publication. Inspected calculation verification and comparisons with uncertain experimental observables for a declared application; source check dated 2026-10-10. Scope is limited to the cited statements, equations and assumptions, not the whole publication.
2026-10-10 · Author source inspection of the displayed claim, model assumptions and equations; independent exact-content and branch-inventory review is a separate gate. Contemporary status is a dated snapshot, not a promise of ongoing monitoring.
Entry details
Permanent link to this entry ↗- Record identity
- research-measurement-model-discrepancy-budget
- Revision
- research.1
- Structured reference record
- Postgraduate & research reference