For example, the weights of two objects weighed by the analytical balance are 1.5268g and 0. 1526g respectively. Assuming that the true values of the two objects are 1.5267g and 0. 1525g respectively, the absolute errors of the two objects are as follows:
e 1 = 1.5268- 1.5267 =+0.000 1g，E2 = 0. 1526-0. 1525 =+0.000 1g .
Relative error formula
(δ-actual relative error, generally given as a percentage, δ-absolute error, L- truth value).
Extended data
1, absolute error
Let the measured value of a physical quantity be X and its true value be A, then X-A = ε; The error ε expressed by this formula has the same unit as the measured value X, which reflects the deviation between the measured value and the true value, so it is called absolute error (the absolute value of the difference between the measured value and the true value).
If the upper bound of its absolute value is estimated, ε(x*) is called the absolute error limit of approximation number x*, which is abbreviated as ε *. Mathematical definition: in the measurement, we do not consider the size of a certain quantity, but only the size of the error between its approximate value and its accurate value. Absolute error is positive and negative, with direction.
2. Relative error
Generally speaking, relative error can better reflect the reliability of measurement. Let the measured result y subtract the measured agreed true value t, and the error or absolute error is δ. The relative error can be obtained by dividing the absolute error δ by the agreed truth value t.
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