Absolute Error

The Difference between the measured or inferred value of a quantity $x_0$ and its actual value $x$, given by

$$\Delta x\equiv x_0-x$$

(sometimes with the Absolute Value taken) is called the absolute error. The absolute error of the Sum or Difference of a number of quantities is less than or equal to the Sum of their absolute errors.

See also Error Propagation, Percentage Error, Relative Error

References

Abramowitz, M. and Stegun, C. A. (Eds.). Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables, 9th printing. New York: Dover, p. 14, 1972.