The most accurate method of quantifying a market would be to carry out a census of all the individuals or organisations who are active within it. However, apart from some industrial markets in which the number of purchasers is very small, a census is rarely practical. Nor, in the past, have they been economic though the ever-widening use of electronic point of sale (EPOS) equipment has facilitated the collection of purchase data from censuses of retail customers. Fortunately, in the post-war period statistical methods have advanced to the point where samples of the participants in any market can provide data which, though not completely accurate, is sufficiently accurate for marketing decision making.
Unable to display preview. Download preview PDF.