ABSTRACT
This chapter covers the differences between judgmental and statistical sampling, the applicability of both in audit practice, and the dangers inherent in confusing the two. The differences in selection methods are covered as well as their impact on the analysis and interpretation possible within the sampling methods. The statistical sampling approach is intended to produce a sample that can be expected to be representative of the population. Common non-statistical selection techniques include judgmental selection in which the auditor uses his or her judgment to place a bias on the sample based on their previous experience. Once again, due to its non-statistical nature, extrapolation of results to the population is unreliable and should be avoided. A major form of statistical error comes from threats to the internal validity of the sampling. The external validity of the population is commonly assumed, permitting findings to be generalized across populations, settings, and time.
