ABSTRACT
A perfect sample would be like Grandview: a “scaled-down” version of the population, mirroring every characteristic of the whole population. In an ideal survey, the sampled population will be identical to the target population, but this ideal is rarely met exactly. Shere Hite’s sampled population was women belonging to women’s organizations who would return the questionnaire. A good sample will be as free from selection bias as possible. Purposive or judgment samples can provide valuable information, though, particularly in the early stages of an investigation. A good sample has accurate responses to the items of interest. If studying the transport of pollutants from coastal waters to the deeper waters of the ocean, a sampling scheme that ignores the boundary effect may underestimate the amount transported. Sampling is the science and art of controlling and measuring the reliability of useful statistical information through the theory of probability”.
