Composite sampling

In sampling certain types of materials, such as bags of fertilizer, or subsampling large quantities of water, as might be done in investigating the density of plankton in certain environmental situations, it is customary to composite the samples. That is, several samples are drawn, mixed into a composite sample, and a sample taken from the composite is then used to determine relevant characteristics of the population. In this paper the results of Brown and Fisher [1972] are extended to more complex situations (e.g., more than one variance component present).