Appendix 4: Measurements

Question 1

Accuracy

Answer 1

Measure of the closeness of agreement between an individual test result and a true value.

Question 2

Anomaly

Answer 2

Value in a set of results that is judged not to be part of the inherent variation

Question 3

Confidence

Answer 3

Qualitative judgement expressing the extent to which a conclusion is justified by the quality of evidence

Question 4

Error

Answer 4

Difference between an individual measurement and the true value of the quantity being measured

Question 5

Precision

Answer 5

Closeness of agreement between independent measurements obtained under the same conditions

Question 6

Repeatability

Answer 6

Precision obtained when measurements are produced over a short timescale by different people by one person using the same equipment in the same setting

Question 7

Reproducibility

Answer 7

Precision obtained when measurement results are produced over a timescale by different people using equivalent equipment in different places

Question 8

Resolution

Answer 8

Smallest change in the quantity being measured

Question 9

Uncertainty

Answer 9

Estimate attached to a measurement which characterises the range of values

Question 10

Validity

Answer 10

An experiment is valid if it measures what it’s supposed to be measuring