Term: harmonic mean
https://doi.org/10.1351/goldbook.H02745

Definition:
The number of observations, divided by the sum of reciprocals of the observations. Symbol: x ̄ h. It can be calculated with the formula: \[\bar{x}_{\text{h}} = \frac{n}{\sum x_{j}^{-1}}\]

Note: As in the case of the geometric mean, this quantity is sometimes directly (but inappropriately) calculated, for example, when evaluating kinetic analytical results where the @R05179@ is inversely proportional to concentration.

Related Terms:
1) reaction time (http://doi.org/10.1351/goldbook.R05179).

Source: PAC, 1994, 66, 595. 'Nomenclature for the presentation of results of chemical analysis (IUPAC Recommendations 1994)' on page 602 (https://doi.org/10.1351/pac199466030595)

Citation: 'harmonic mean' 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.H02745

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