Good evening everyone,

Conceptually i'm clear on the difference between accuracy and precision. However, I wonder in which all situations a process can be accurate but not precise?

Is it equivalent to state that if a process is running within the control limits but still not touching the target? ie a process has a good Cp Short term but poor long term?

Some pratical examples/ scenario from service industry are welcome.

Regards,

Shalini

Hi Shalini, 

Accurate means average same as targeted value.

Precise means low variation

A broadband connection that has OK speed on an average but large variation can be taken as an example for "ACCURATE BUT NOT PRECISE"

Regards,

VK 

so is it safe to infer that any process having only common cause variation is accurate but not precise? and also an accuarte but not presise process will have a good Cpk but poor Ppk?

'M I linking too many parameters at the same time? request you to clear this fog pse !

Dear Shalini, 

Accuracy and Precision as terms are mostly used in Measurement System Analysis, where we want accuracy and precision at the same time. 

If multiple measurements are taken for the same item, the readings should not have much variation (precise) and the average should be as close to true value as possible (accurate). 

Have a look at explanation on Wiki -  click here

Regards, 

VK