IEC TR 63250-2021 pdf Household and similar electrical appliances – Method of measuring performance – Assessment of repeatability, reproducibility and uncertainty

3.8 reproducibility standard deviation: standard deviation of test results or measurement results obtained under reproducibility conditions Note 1 to entry: It is a measure of the dispersion of the distribution of test or measurement results under reproducibility conditions. Note 2 to entry: Similarly, “reproducibility variance” and “reproducibility coefficient of variation” can be defined and used as measures of the dispersion of test or measurement results under reproducibility conditions. [SOURCE: ISO 3534-2:2006, 3.3.1 2 modified – Cross-references have been deleted] 3.9 outlier member of a small subset of observations that appears to be inconsistent with the remainder of a given sample Note 1 to entry: The classification of an observation or a subset of observations as outlier(s) is relative to the chosen model for the population from which the data set originates. This or these observations are not to be considered as genuine members of the main population. Note 2 to entry: An outlier may originate from a different underlying population, or be the result of incorrect recording or gross measurement error. Note 3 to entry: The subset may contain one or more observations. [SOURCE: ISO 1 6269-4:201 0, 2.2 modified – Cross-references have been deleted] 3.1 0 statistical uncertainty repeatability standard deviation obtained in one laboratory under repeatability conditions 3.1 1 expanded uncertainty quantity defining an interval about the result of a measurement that may be expected to encompass a large fraction of the distribution of values that could reasonably be attributed to the measurand Note 1 to entry: The fraction may be viewed as the coverage probability or level of confidence of the interval. Note 2 to entry: To associate a specific level of confidence with the interval defined by the expanded uncertainty requires explicit or implicit assumptions regarding the probability distribution characterized by the measurement result and its combined standard uncertainty.
5.3 Expression of repeatability and reproducibility Reproducibility standard deviation can be a value of absolute or relative nature. Depending on the nature of the error, either one or the other shall be preferred. Absolute values of the reproducibility standard deviation shall be preferred when the measurement error is not likely to be influenced by the absolute value of the measurand. Relative values are preferred when the error will grow or diminish with the absolute magnitude of the measurand.