ABSTRACT
Sampling is a process whereby a small part of any population is selected for observation to estimate a given characteristic of the entire population. Sampling is used to estimate a population parameter. Sample statistics are quantities derived from the sample. A sampling strategy is the procedure by which the sample is derived from the population. A desirable sampling strategy provides an estimate that is close to the true value of the population characteristic. In stratified sampling, the population is divided into subsets, or strata, and samples are selected at random from within each stratum. Sampling techniques differ as functions of the size of the population being sampled. Incremental sampling techniques are implemented on unmovable lots, and sample-splitting methods are implemented on movable lots. Errors in the estimation of population parameters may be sampling or nonsampling errors. Nonsampling errors include the errors that occur during sample preparation, analysis, or measurement.
