Public opinion poll

Public opinion poll, technique for measuring the range of opinions held by the general public or by specifically limited groups of people. It developed during the 1920s. Opinion polls rely on certain statistical laws that show that small, carefully chosen samples of any group can accurately represent the range of opinions of the whole group, or population. The population in question, known as the “ universe,” may be a general one (all voters in the United States) or a limited one (all car workers in Detroit). Accuracy depends on the care with which the sample is constructed and on the size of the sample. Since 1944 all polls have adopted the method of random selection pioneered by the U.S. Census Bureau in which each member of the “ universe” has an equal chance of being questioned. Pioneers in U.S. public-opinion polling include George Gallup, Louis Harris, and Elmo Roper.