Education

Difference between Accuracy and Precision

Main Difference

The main difference between accuracy and precision is that accuracy refers to the degree to which the measurement or calculation conforms to the exact value. Accuracy is exactness, validity and perfection. While precision is the attribute of the calculation to be consistently reproduced. Precisely, accuracy is very much close to exactness and correctness while precision lacks a block or two.

Accuracy

accuracyIn a strict sense of view, accuracy shows how close a calculation is to the value that is given.  Broadly stating, accuracy is very close to the target. The accuracy, for instance, of an experimental object is the value of how close the results match to the actual or known value given. Accuracy is also used as a statistical measure and it is the collection of true results rather than false ones. If the accuracy is of hundred percent then it concludes that calculated values are same as the given values.

Precision

precisionOn the other hand, precision is the number of true positives against the number of both, true and false positives. It actually refers to what is the degree to which something is strictly exact. Even if the measurements are far from the given value, precision indicates how reproducible they really are. And as for hitting the target, precisely hitting the given target means that all the arrows hit are spaced closely even if they are far from the main target.

Key Differences

  • Accuracy is correctness, while precision is close to exactness.
  • Precision may denote the quality of an instrument, highly. While accuracy will not show the quality.
  • There is a chance of further improvement in accuracy by taking repeated measurements and by doing repeated calculation. But, in the case of precision, it could not be improved by doing repeated calculations.
  • Mathematically stating, accuracy is actually the degree of closeness to the given answer or value while precision is the degree of deviation from the original given result
  • An accurate value can also be precise. But a precise value cannot be accurate.
  • A value can be accurate occasionally, in a strict sense of view. But, a value can be precise many times.
  • In accuracy, a single factor is needed. While in precision, multiple factors are needed.
  • One cannot achieve accuracy without precision. But, precision could be achieved without accuracy.

Video Explanation