Question

Look in the newspapers, magazines, and other news sources for results of a survey or poll that show the confidence interval, usually shows as a +/- some amount. Describe the survey or poll and then describe the interval shown. How does knowing the interval, rather than just the main result, impact your view of the results?

Answer 1

Example is of an opinion poll in the U.S.

An opinion poll on small sample of Americans via telephone on a particular topic. The results showed that 66% approved and 30% disapproved among the sample. here margin of error is 4.5%. So confidence interval is from 61.5% to 70.5%. Use and meaning of Interaval:- So the percentage in population approving the decision will likely to be between 61.5% and 70.5%. So, The estimated confidence interval provides a range of values between which true population value lies long with certain probability (confidence level).