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How reliable is my uncertainty estimate?
Analytical Methods : Advancing Methods and Applications
|June 10, 2021
Summary
Laboratories report measurement uncertainty (MU), but this MU value is an estimate, not exact. This estimate of MU also has its own uncertainty, often expressed as a confidence interval.
Area of Science:
- Analytical Chemistry
- Metrology
- Laboratory Science
Background:
- Laboratories routinely report measurement uncertainty (MU) for measured quantities.
- MU quantifies the range where the true analyte concentration (measurand) is expected to lie.
Purpose of the Study:
- To highlight that the reported MU is an estimate, not an exact value.
- To introduce the concept that MU itself possesses uncertainty.
Main Methods:
- Conceptual analysis of measurement uncertainty estimation.
- Discussion of statistical representation of uncertainty.
Main Results:
- The reported MU is an estimate with inherent uncertainty.
- This uncertainty of MU can be quantified using confidence intervals (CI).
Conclusions:
- The uncertainty of measurement uncertainty requires careful consideration in laboratory reporting.
- Confidence intervals provide a method to express the uncertainty associated with MU estimates.
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