## klimenkov 2 years ago What is the difference between accuracy and precision?

1. rizwan_uet

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2. rizwan_uet

you have two figures X and Y. these figures are considered as field targets to a shooter. For target X the three shots are close to the center but they are inconsistent among each other. these shots are said to be accurate

3. rizwan_uet

now for figure Y the shots are close among each other but away from the center thus it is said that these shots are precise but not accurate.

4. rizwan_uet

we conclude that if we have a set of readings and those readings are far away from the actual value but close to each other then the readings are said to be precise. but if the readings are far away from each other but close to the actual value then these readings are said to more accurate and less precise.

5. klimenkov

Do the words "accuracy" and "precision" mean the same in English?

6. rizwan_uet

no these are completely different terms

7. rizwan_uet

accuracy means how close you are to the actual value and precision means how close are set of values to each other.

8. klimenkov

When I open the vocabulary and translate "accuracy" I is translated as "точность" in Russian, and when i find the word "precision" it is translated as "точность" too. But now I think I understand it. How can I apply this to the consecutive approximations for $$\sqrt 2$$ for example? 1) 1 2) 1.5 3) 1.4 4) 1.41 ... What can you say about precision and accuracy in this case?

9. sauravshakya

The more decimal places the more precise it is. And the more it is closer to the true value the more accurate it is.

10. rizwan_uet

sqrt (2) = 1.4142.... you have these choices 1) 1 2) 1.5 3) 1.4 4) 1.41 the choice (4) is more close to the actual value and has more decimal places thus this choice is more accurate and more precise as well.

11. klimenkov

So, if I have the sequence $$a_n$$ for approximations for $$\sqrt2$$, then $$|a_{n+1}-a_n|$$ is precision and $$|\sqrt2-a_n|$$ is accuracy. Am I right?

12. rizwan_uet

yes exactly

13. klimenkov

Thank you. In Russian there is no analogy for this situation. In any of these cases it is called "точность".

14. rizwan_uet

you are welcome. by the way are you Russian???

15. klimenkov

Actually, I live in Ukraine. But the biggest part of the population speaks Russian.

16. rizwan_uet

ok. i will fan you. nice to talk to you.

17. Dean.Shyy

Accuracy is closeness to target, while precision is aggregated accuracy involving a target or not.