Term: precision
https://doi.org/10.1351/goldbook.P04799

Definition:
The closeness of agreement between independent test results obtained by applying the experimental procedure under stipulated conditions. The smaller the random part of the experimental errors which affect the results, the more precise the procedure. A measure of precision (or imprecision) is the standard deviation.

Note: As recognized in VIM, precision is sometimes misused for @A00060@. This problem will be avoided if one recognizes that precision relates only to dispersion, not to @D01650@ from the (conventional) true value. Imprecision has been defined as 'the standard error of the reported value'.

Related Terms:
1) standard deviation (http://doi.org/10.1351/goldbook.S05911).
2) accuracy (<em>of measurement</em>) (http://doi.org/10.1351/goldbook.A00060).
3) deviation (<em>of measurement</em>) (http://doi.org/10.1351/goldbook.D01650).

Source: Orange Book, 2nd ed., p. 6 (https://media.iupac.org/publications/analytical_compendium/)

Citation: 'precision' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.P04799

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