5. Accuracy

Accuracy

Accuracy refers to how close a representation of a value is to the true value.

Relative error is a measure of accuracy of a representation. Relative error = $\frac{|T-R|}{T}\times 100$, where $T$ is the true value and $R$ is the value that is represented.

For example, we know there is no exact representation of $0.3_{10}$ in binary:

• In 5-bit fixed-point binary, with point between 4-3, the most accurate is $0.0100_2=0.25_{10}$. The accuracy is $\frac{|0.3-0.25|}{0.3}\times 100=16.67\%$.