Random sampling and the principles of estimation

Judgement sampling in market research and opinion polling is standardly criticized as unsatisfactory on the grounds of its subjectivity, and it is widely held that random sampling is the only scientific means of investigating properties of large populations. This paper investigates these claims. It concludes that the principle of random sampling is not well founded. It also argues that Bayesian theory, which allows judgement samples, provides an intuitively correct basis for investigating population properties