Difference Between Trueness & Bias Measurement

[Roger Dodger]

Can someone explain the difference between trueness and bias, as used in measurement?

 

[jedishrfu]

As in accuracy and precision?

https://en.m.wikipedia.org/wiki/Accuracy_and_precision

Say you have a target and all your shots are near and around the center but spread out then you have accuracy but not precision. Another archer steps up and places his shots in a tight spread that is off center then he/she has precision but not accuracy.

Robin Hood steps up and shoots all his arrows dead center in a tight spread and so he has accuracy and precision.

 

[Roger Dodger]

I understand the distinction between accuracy and precision. However, the terms trueness and bias seem almost interchangeable and I am hoping someone can clarify the difference.

 

[jedishrfu]

It seems trueness is accuracy but I don’t have an immediate reference for that. Perhaps an online dictionary would clarify it.

Heres one reference on bias vs precision

https://cals.arizona.edu/classes/rnr613/accuracy.html

 

[jedishrfu]

I found this also

https://www.astm.org/SNEWS/MARCH_2000/P&B_mar00.html

 

[Roger Dodger]

I appreciate the references, but the distinction between trueness and bias is what I seek.

 

[jedishrfu]

Okay last try

https://www.iso.org/obp/ui/#iso:std:iso:5725:-1:ed-1:v1:en

Your best bet after this is to do some searching yourself using google or your university library.

 

[Roger Dodger]

Yes, I tried that.

 

[Roger Dodger]

It appears I missed this:

"The term bias has been in use for statistical matters for a very long time, but because it caused certain philosophical objections among members of some professions (such as medical and legal practitioners), the positive aspect has been emphasized by the invention of the term trueness."

That explains it.

 

[jedishrfu]

That's great where did you find that quote?

 

[Roger Dodger]

It's at the bottom of the ISO link you provided.

 

[WWGD]

I appreciate the references, but the distinction between trueness and bias is what I seek.

How do you define each?

 

[Roger Dodger]

According to what I see, bias is now trueness. Their meanings are not distinct.