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Published on Apr 5, 2010
The census is expensive, takes time and entails a great deal of labour. George Gallup, from 1928, introduced probability sampling into the world of commercial research. In the 1940s, the US Department of Agriculture developed a probability method for sampling households and individuals. Until 1990, the main source of general population samples in the UK was the Electoral Register, then millions of people refused to pay Poll Tax, and did not Register for voting. This left the Register incomplete, and the postcode address file (PAF) became the sampling frame of choice. http://www.oxfordtextbooks.co.uk/orc/...