Definitions of Accuracy and Precision

Accuracy

The accuracy of a measurement is how close a result comes to the true value. Determining the accuracy of a measurement usually requires calibration of the analytical method with a known standard.

Precision

Precision is the reproducibility of multiple measurements. It is usually described by the standard deviation, standard error, or confidence interval. A separate document defines these quantitative measures of precision.

Illustration of accuracy and precision

Related topics:

• data handling