Metrological comparability and compatibility
Results for quantities of the same kind are metrologically comparable when traceable to the same reference.
Key knowledge
Results for quantities of the same kind are metrologically comparable when traceable to the same reference. For the same specified measurand, a compatibility criterion compares |y₁−y₂| with a chosen multiple of u(y₁−y₂), including covariance: u²(y₁−y₂)=u₁²+u₂²−2cov(y₁,y₂).
Values and equations
u²(y₁−y₂)=u₁²+u₂²−2cov(y₁,y₂); |y₁−y₂|<k u(y₁−y₂)
- y₁,y₂,u₁,u₂,u(y₁−y₂)
- Values and standard uncertainties; common quantity unit
- cov(y₁,y₂)
- Shared-result covariance; squared quantity unit
- k
- Chosen dimensionless comparison multiple
Conditions and scope
- Same kind/reference for comparability; same measurand, stated multiple and valid joint uncertainty for compatibility.
- Common standards can correlate results. Compatibility is not proof of equality or correctness, and an incompatibility requires investigating the measurand/model and uncertainties.
Sources · 2
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
- International Vocabulary of Metrology (VIM3)Joint Committee for Guides in Metrology (JCGM)Reference guideVIM3 2.46: metrological comparabilityVIM3 2.47: metrological compatibility
Evidence and review
VIM3 2.46: metrological comparability: Definition 2.46 and its displayed notes. VIM3 2.47: metrological compatibility: Definition 2.47 and its displayed notes.
2026-10-10 · Independent AI editorial review: Independent root AI editorial review of all29 authored Measurement claims/conditions, displayed equations and37 origin relations. The original26 claims were read against41 primary source sections; all5 requested corrections and the3 affected source bindings were subsequently rechecked. Three actual scalar-nonlinear/vector/dynamic applications were read, independently differentiated or integrated, and checked against the specific additional source material described below. This is reference-content review, not human specialist certification, instrument certification or experimental replication. Full-field sign-off waits for the combined final conceptual matrix. Receipt: measurement-independent-content-review.1.
Entry details
Permanent link to this entry ↗- Record identity
- measurement-comparability-compatibility
- Revision
- university-core.1
- Structured reference record
- University core expansion