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accuracy and precision Question
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Posted by: lakna_3581

03/18/2005, 04:48:55

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can any one clarify me the difference between accuracy and precision with examples..






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Re: accuracy and precision
Re: accuracy and precision -- lakna_3581 Post Reply Top of thread Forum
Posted by: swearingen

03/22/2005, 22:37:32

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The way it was explained to me, accuracy has to do with how close you are to your target value, where precision has to do with how well you can repeat the same value. Example:

At the firing range -

If you shoot all over the target, you're neither accurate, nor precise.

If you shoot a relatively wide grouping around the bullseye, you're accurate, but not precise.

If you shoot all your shots through the left side of the third ring, you're precise, but not accurate.

If you shoot everything very near the bullseye, you're both accurate and precise.







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Re: accuracy and precision
Re: accuracy and precision -- lakna_3581 Post Reply Top of thread Forum
Posted by: randykimball
Barney
03/19/2005, 13:34:20

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According to Thorndike-Barnhart they are almost the same thing, and can be exchanged in conversation.

I would say, "This is a precision product". or "This product was machined with accuracy".

IE: Most pistons diameters for internal cumbustion engines are machined in an oval shape to allow for heat expansion, within an accuracy of less than .0008".

IE2: A NASCAR driver must be able to pick a line and speed to suit the track and car set-up, and must maintain it with extreme precesion to be competitive.

-randy-




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