Correct sampling

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During sampling of granular materials (whether airborne, suspended in liquid, aerosol, or aggregated), correct sampling is defined in Gy's sampling theory as a sampling scenario in which all particles in a population have the same probability of ending up in the sample. [1]

The concentration of the property of interest in a sample can be a biased estimate for the concentration of the property of interest in the population from which the sample is drawn. Although generally non-zero, for correct sampling this bias is thought to be negligible. [1]

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References

  1. 1 2 Gy, Pierre (1979). Sampling of particulate materials : theory and practice. Developments in geomathematics. Amsterdam: Elsevier Scientific Pub. Co. ISBN   0-444-41826-1. OCLC   5101118.