Prior to discussing how to calculate absolute error, let us define error. In statistics, error refers to the difference between the computed value and the correct value. Errors are brought about by rounding off values, truncation just to name a few.
Absolute error is the magnitude of how far off a measurement is from a true value or an indication of the uncertainty in a measurement. Absolute error value is not enough as it does not give any details regarding the importance of the error.
For instance, in large quantities, small errors in centimeters are negligible whereas, when measuring the length of machine parts, the error of centimeters is large.
Sometimes you’ll see the formula written with the absolute value symbol because sometimes the measurement will be smaller, giving a negative number.
Formula to Calculate Absolute Error.
Example 1:
Tobby’s actual mass is 68Kg. His measured mass is 68.3 Kg. Determine the absolute error in his mass.
Thus, the absolute error is 0.3 Kg.
Example 2:
Suppose you measured your weight on a scale and found it to be 160 pounds, if your true weight is 160.2 pounds, calculate the absolute error.
Absolute error = |Measured Value – Actual Value|
= |160 – 160.2|
= |-0.2|
Hence, the absolute error is 0.2 pounds.
