In the fields of science, engineering, industry and statistics, accuracy is the degree of conformity of a measure or calculated quantity to its actual (true) value. Accuracy is closely related to precision, also called reproducibility or repeatability, the degree to which further measurements or calculations show the same or similar results. The results of calculations or a measurement can be accurate but not precise; precise but not accurate; neither; or both. A result is called valid if it is both accurate and precise. The related terms in survey are error (random variability in research) and bias (non-random or directed effects caused by a factor or factors unrelated by the independent variable).
Accuracy vs precision - the target analogy
Accuracy is the degree of veracity while precision is the degree of reproducibility. The analogy used here to explain the difference between accuracy and precision is the target comparison. In this analogy, repeated measurements are compared to