Difference Between Accuracy and Precision

Key Difference – Accuracy vs Precision

 

The terms accuracy and precision are two words between which a key difference can be highlighted although both are often encountered in the fields of engineering, physics, and industry. The accuracy of a measurement means getting a value that is close to the actual answer. Precision, on the other hand, refers to the reproducibility of this result that is you get the same result every time you try. Even this clear cut demarcation does not stop people from relating these two concepts and talk of them in similar terms. However, accuracy and precision are as different as cheese and chalk that will be clear to the readers after reading this article.

What is Accuracy?

As mentioned in the introduction accuracy of a measurement means getting a value that is close to the actual answer. Have you ever played darting as a kid? Yes, the same game where there is a circular target that is pinned on a wall and kids try to hit the centre of the target that fetches them maximum points. Now if a kid hits the centre, he is said to be accurate. This is because the child is able to hit directly the target correctly. Hence, it highlights maximum accuracy.

If a person is just less than 6 feet in height, he would not like to be so accurate as to say he is 5 feet 11 and three-quarters of an inch in height which would also look troublesome for anyone to understand. So he can sacrifice accuracy in favor of a number that is easier to speak and also to remember. Had you used millimeters to describe your height, you could have done it more accurately.

Difference Between Accuracy and Precision

What is Precision?

Precision refers to the reproducibility of this result that is you get the same result every time you try. Let us use the same example of the child hitting a dart board in order to understand the difference between accuracy and precision. As mentioned earlier if the child is able to hit the target, he is considered as accurate and if he happens to hit the centre regularly, he is also precise, which is to say that he is hitting bull’s eye all the time.

Precision unlike in the case of accuracy is not limited to a single situation, on the other hand, it comes with reproducibility as the definition suggests. Now that you know the difference between accuracy and precision, you must also know that the results of calculation or a measurement can be accurate but not precise, precise but not accurate, neither, or both. Any measurement system is valid only if it is both accurate as well as precise.

This highlights that in usage one should be careful whether to consider a situation as accurate or precise as they contain different meanings. This difference between the two words can be summarized as follows.

Accuracy vs Precision

What is the Difference Between Accuracy and Precision?

Definitions of Accuracy and Precision:

Accuracy: Accuracy of a measurement means getting a value that is close to the actual answer.

Precision: Precision refers to the reproducibility of this result that is you get the same result every time you try.

Characteristics of Accuracy and Precision:

Nature:

Accuracy: Accuracy refers to the closeness of a measurement to its actual or real value.

Precision: Precision refers to the regularity of obtaining the same result frequently.

Usage:

Accuracy: The concept of accuracy is encountered in measurement in physics and industry.

Precision: The concept of precision similar to accuracy is also encountered in measurement in physics and industry

 

 

 

Image Courtesy:

1. “High accuracy Low precision” by DarkEvil – [Public Domain] via Wikimedia Commons

2. Precision Guided Firearm By photographer Oren Schauble (Oren Schauble (via email)) [CC BY-SA 3.0], via Wikimedia Commons