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2 concepts, 1 accuracy, precision, and resolution – Campbell Scientific CR800 and CR850 Measurement and Control Systems User Manual

Page 449

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Section 11. Glossary

449

 

11.2 Concepts

11.2.1 Accuracy, Precision, and Resolution

Three terms often confused are accuracy, precision, and resolution. Accuracy is a
measure of the correctness of a single measurement, or the group of
measurements in the aggregate. Precision is a measure of the repeatability of a
group of measurements. Resolution is a measure of the fineness of a
measurement. Together, the three define how well a data-acquisition system
performs. To understand how the three relate to each other, consider "target
practice" as an analogy. Figure Accuracy, Precision, and Resolution

(p. 449)

shows

four targets. The bull's eye on each target represents the absolute correct
measurement. Each shot represents an attempt to make the measurement. The
diameter of the projectile represents resolution. The objective of a data-
acquisition system should be high accuracy, high precision, and to produce data
with resolution as high as appropriate for a given application.

Figure 130: Accuracy, Precision, and Resolution