sentence: Scientists commonly report the standard deviation of numbers from the average number in experiments.
sentences_before: Standard deviation is also used to measure how close a reported number is to being exactly right. For example, the standard deviation is used to find margin of error in opinion poll numbers. The reported margin of error is usually two times the standard deviation and gives the range for the true poll number.
sentences_after: They often decide that only differences bigger than two or three times the standard deviation are important.
concept_name: scientist
headings: Standard deviation
categories: Statistics