That part of the total error (the estimate from a sample minus the population value) associated with using only a fraction of the population and extrapolating to the whole, as distinct from analytical or test error. It arises from a lack of homogeneity in the parent population. In chemical analysis, the final test result reflects the value only as it exists in the @T06284@. It is usually assumed that no sampling error is introduced in preparing the @T06285@ from the @L03433@. Therefore, the sampling error is usually associated exclusively with the variability of the @L03433@. Sampling error is determined by @R05300@ of the laboratory samples and their multiple analyses. Since sampling error is always associated with analytical error, it must be isolated by the statistical procedure of analysis of variance.