Opinion polling

An opinion poll or survey asks specific questions of a random sample or a specific quota of the public. This process provides objective statistics of public opinion. With large enough samples of the public, differences in the hopes, fears, and priorities of different groups can be compared. Polls are useful for exploring attitudes and registering preferences and priorities about specific sets of choices. All polls based on samples are subject to sampling error which reflects the effects of chance in the sampling process. The uncertainty is often expressed as a margin of error. The margin of error does not reflect other sources of error, such as measurement error.