Sampling Methodologies Comptroller's Handbook August 1998

It is usually impractical or impossible to review all items or files when examining an area of bank operations, especially if the volume of information is large. Examiners use sampling to observe a random subset to learn about the multitude of items from which they are drawn. Upon drawing statistical inferences from this subset, they can state with a certain level of confidence that the inferences apply to the population as a whole.