Accuracy
Accuracy
Accuracy is the degree to which a measurement aligns with its true, actual value
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It represents freedom from error and consistency to a recognised standard
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Improving data quantitation (making the data less qualitative) will improve accuracy
The degree of accuracy can be represented by the measurement uncertainty for a given device
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Absolute uncertainty will represent a fixed numerical estimation of error expressed as a range (e.g. ±0.5)
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Relative uncertainty will represent the error as a ratio of an amount expressed as a percentage (e.g. ±2%)
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The relative uncertainty is proportionate to the quantity measured (i.e. larger amount = smaller percentage)
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The accuracy of a data set is influenced by systematic errors (predictable variations in the measurement process)
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Systematic errors create consistent and directional displacements of data values that cannot be reduced by repeating the measurement
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Sources of systematic errors include faulty calibrations of measurement devices or faulty readings by a user (e.g. parallax error)
Accuracy vs Precision
