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The closeness of agreement between a test result and the accepted reference value. 1) In practice, the accepted reference value is substituted for the true value. 2) The term "accuracy," when applied to a set of test or measurement results, involves a combination of random components and a common systematic error or bias component. 3) Accuracy refers to a combination of trueness and precision.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E177-14 Standard Practice for Use of the Terms Precision and Bias in ASTM Test Methods. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2014. Source link
Reprinted, with permission, from ASTM, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard may be purchased from ASTM International,