On sampling and the estimation of rare errors

SUIMM-AY For each individual in a finite population a recorded value is available. A small proportion of the values is in error, all the errors being of the same sign and the maximum fractional error being known. It is required to obtain an upper confidence limit for the total error in the population. Various solutions, including a Bayesian one, are discussed for sampling with probability proportional to the recorded values, and the appropriateness of this form of sampling is examined.