Precision

What is Precision?

Precision refers to the amount of information that is conveyed by a number in terms of its digits; it shows the closeness of two or more measurements to each other. It is independent of accuracy.

Let us understand it with the help of an example;
If you weigh an object five times and you get 3.2 kg every time, then your measurement is very precise. Precision refers to a value in decimal numbers after the whole number, and it does not relate with accuracy. The concepts of accuracy and precision are almost related, and it is easy to get confused.

Precision

Precision is a number that shows an amount of the information digits and it expresses the value of the number.
For Example- The appropriate value of pi is 3.14 and its accurate approximation. But the precision digit is 3.199 which is less than the exact digit. It has numerous forms in statistics, arithmetic, and precision etc.

What is the difference between precision and accuracy?

For instance:

  • A number that is not precise but accurate.
  • A number that is not accurate but precise.
  • A number that is precise and accurate.

Precision is the amount of information that is conveyed by a value. Whereas Accuracy is the measure of correctness of the value in correlation with the information.

Let’s consider the value of “pi”, i.e, 3.142857143.

According to the questions:

A number that is not precise but accurate is 3.14. It is accurate based on closeness and no other number with three digits can get closer to the target.

A number that is not accurate but precise is 1.1423345678901234567890. It is very precise as it conveys more information. But cannot be considered as accurate because it’s not near the target.

A number that is precise and accurate is 3.142857143. It is the only number which has maximum accuracy and precision if the target value is 3.142857143.

Precision

The above figure shows a dart game having three images,

(i) The first one shows Good accuracy and good precision, as all the three darts are are close to maximum score region (accurate) and also all the darts are close to each other (precise).

(ii) The second figure shows Poor accuracy but good precision, as all the three darts are close enough but far away from the maximum score region.

(iii) The third figure shows Poor accuracy and poor precision, as all the darts are neither nearby nor to the maximum score region.

Example:  From the given problem: 12 x 3.45, Find out the precision value.

Solution:

12 x 3.45 is the problem we’ve been given to solve

The consequence of multiplication = 41.4.

Here the decimal or significant digit is one that is the precision value is one.


Practise This Question

16 hemispheres of radius 2 cm are melted to make a single sphere. Find radius of the sphere.