Accuracy and Precision


The term Precision refers to the reproducibility of a result or measurement. The term Accuracy refers to how close a result or measurement is to the actual value. A common analogy is an archer shooting arrows at a target. If the archer shoots three arrows in a tight group, his shooting would be considered precise. The accuracy of the archer would be determined by the location of the group of arrows. If the group were outside the bull's-eye area, the archer would be precise but not accurate. If the arrows found their way to the bull's-eye area, the archer would be both accurate and precise. The goal of any chemist in the laboratory is to achieve both accuracy and precision in their experimental results and measurements.