ISO 3534-2:200: difference between the expectation of the test results and a true value

Note 1 to entry: Bias is the total systematic error as contrasted to random error. There can be one or more systematic error components contributing to the bias. A larger systematic difference from the accepted reference value is reflected by a larger bias value.

Note 2 to entry: The bias of a measuring instrument is normally estimated by averaging the error of indication over an appropriate number of repeated measurements. The error of indication is the ‘’indication of a measuring instrument minus a true value of corresponding input quantity’’.

Note 3 to entry: In practice, the accepted reference value is substituted for the true value

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