Percentage error is primarily a measure of accuracy rather than precision. Accuracy refers to how close a measured value is to the true or accepted value, while precision relates to how consistently repeated measurements produce the same result.
When calculating percentage error, you compare the difference between your measured value and the true value relative to the true value itself. This comparison gives you an indication of how far off your measurement is from what is considered correct, thus assessing accuracy.
For example, imagine you are measuring the length of a table, and the true length is 200 cm. If your measurement is 198 cm, the percentage error can be calculated as:
Percentage Error = |(Measured Value - True Value)| / True Value * 100
= |(198 - 200)| / 200 * 100
= |(-2)| / 200 * 100
= 1%This 1% indicates how accurate your measurement of the table’s length is relative to the true length. If you had taken multiple measurements and they all yielded 198 cm, that would reflect precision, but the percentage error tells us about accuracy in relation to the true value.