Accuracy Definition and 236 Threads

In a set of measurements, accuracy is closeness of the measurements to a specific value, while precision is the closeness of the measurements to each other.
Accuracy has two definitions:

More commonly, it is a description of systematic errors, a measure of statistical bias; low accuracy causes a difference between a result and a "true" value. ISO calls this trueness.
Alternatively, ISO defines accuracy as describing a combination of both types of observational error above (random and systematic), so high accuracy requires both high precision and high trueness.Precision is a description of random errors, a measure of statistical variability.
In simpler terms, given a set of data points from repeated measurements of the same quantity, the set can be said to be accurate if their average is close to the true value of the quantity being measured, while the set can be said to be precise if the values are close to each other. In the first, more common definition of "accuracy" above, the two concepts are independent of each other, so a particular set of data can be said to be either accurate, or precise, or both, or neither.

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  1. Agent Smith

    B Test of statistical significance

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  2. Agent Smith

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  3. S

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  4. S

    B Which science communicator do you find to maintain the most accuracy?

    Was watching a Sean Carroll video and his answers to some questions seemed to run counter to the norm. For example at 1:15:30 in the video, he seems to be saying that we'd see only a (hypothetical?) 'test particle' get stuck at the event horizon of a black hole. Also at 1:17:19 in the video...
  5. Govind

    I Measurement Error Analysis in Gaussian distribution

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  6. RobbyQ

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  7. Conn_coord

    I Measurement accuracy or variation

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  8. tomceka

    How does the accuracy of the clock change when the spring stretches?

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  9. shivajikobardan

    Why did I get different accuracy for different algorithms?

    Here are the codes(not all might be present, take it with grain of salt). https://github.com/prabesh-regmi/Employee-Promotion-Prediction
  10. H

    A What is the achievable accuracy of neutrino speed measurement?

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  11. F

    How to select the required accuracy of an instrument?

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  12. F

    Instrument accuracy and comparison measurements

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  13. mcastillo356

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  14. B

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  15. C

    Did your DNA test results change when using a second company to do the test?

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  16. J

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  17. G

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  18. LittleRookie

    B How is a Scientific law/theory's accuracy tested?

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  19. L

    How Is Error Managed When Measuring the Difference Between Two Values?

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  20. S

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  21. W

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  22. BillTre

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  23. J

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  24. M

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  25. C

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  26. bland

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  27. P

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  28. A

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  30. W

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  31. A

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  32. J

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  34. P

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  35. A

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  36. Sebastiaan

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  37. alphaj

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  38. S

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  39. Xilus

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  40. A

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  41. bknock

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  42. U

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  43. U

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  44. N

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  45. B

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  46. E

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  47. Crowxe

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  48. S

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  49. Jamison Lahman

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  50. Deebu R

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