accuracy
Correctness means that a statement is correct . Terms such as validity , correctness , truth , and flawlessness occur synonymously . The question of correctness arises in all areas of knowledge.
In technology , quality assurance and statistics , the term is used to assess measured values and determination values, including the associated procedures. Here, correctness is understood as a designation for the extent to which an expected value approaches a correct or true value .
Etymology and meaning
Correctness ( Late Middle High German : richticheit ) has been documented in German in the meaning of "being correct" since the 15th century. Today's meaning is "appropriateness, order". The underlying adjective correct can be proven as rihtig in Old High German of the 11th century, in Middle High German as rihtec, rihtic, rihtig . It originally meant "straight, aligned with the guiding principle" and takes on direct reference, not directly on right , in today's parlance is correct as the antonym of incorrectly used. Opposite words to the noun are falsehood , inaccuracy and untruth .
measuring technology
The arithmetic mean of measured values from incessantly repeated measurements under given conditions tends towards the expected value with increasing number. The term accuracy (Engl. Trueness) is coming a qualitative designation as close to the expected value of a reference value (true or correct value). Conversely, how far these values are, says the systematic deviation . It is this quantity that is used for quantitative statements about correctness. A small measurement deviation corresponds to a high approximation in measurement technology . A systematic measuring device deviation caused solely by a measuring device can be corrected (technical term: adjusting the device ). In practice, e.g. B. in legal metrology, a measuring device is considered correct if its systematic measuring deviations are within defined error limits .
The accuracy must be distinguished from the precision (precision) that the degree of convergence of individual values with each other at scattering designated. A high mutual approximation of the measured values means small random deviations .
The accuracy denotes the extent to which the individual values approximate the reference value. According to this definition, a result is then accurate if it is both correct and precise - if there is both a small systematic measurement deviation and a small standard deviation (or other measure of scatter).
Correctness and precision using the example of several shots from different rifles
Correctness and precision good (good accuracy)
Correctness good, but poor precision (poor accuracy)
Precision good, but bad trueness (poor accuracy)
Poor precision and trueness
(poor accuracy)
Data density distribution; Differentiation of the deviations from the correct value
Web links
Individual evidence
- ↑ a b DIN 55350-13: 1987 Terms of quality assurance and statistics; Terms for the accuracy of investigation procedures and investigation results
- ↑ DIN ISO 5725 Accuracy (correctness and precision) of measurement methods and measurement results ; Several parts
- ↑ a b JCGM 200: 2012 International vocabulary of metrology - Basic and general concepts and associated terms (VIM) , No. 2.14. (PDF; 3.8 MB)
- ↑ a b c DIN 1319-2: 2005 Basics of measuring technology - Part 2: Terms for measuring equipment
- ↑ a b after Duden "Etymologie" - dictionary of origin of the German language , 2nd edition, Dudenverlag, 1989
- ↑ Mackensen - Large German Dictionary , 1977
- ^ Etymology adjective correct according to Kluge Etymological Dictionary of the German Language , 24th edition, 2002
- ↑ a b DIN 1319-1, Fundamentals of measurement technology - Part 1: Basic concepts , 1995