Kipp&Zonen BSRN Scientific Solar Monitoring System User Manual
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Influence quantity
Quantity that is not the m easurand but that affects the result of the m easurem ent.
Result of Measurement
Value attributed to a m easurand, obtained by m easurem ent.
Notes:
a.
W hen a result is given, it should be m ade clear whether is refers to:
i.
the indication
ii.
the uncorrected result
iii.
the corrected result and whether several values are averaged
b.
A com plete statem ent of the result of a m easurem ent includes inform ation about the uncertainty.
Uncorrected result
Result of a m easurem ent before correction for system atic error.
Corrected result
Result of a m easurem ent after correction for system atic error.
Accuracy of measurement
Closeness of the agreem ent between the result of a m easurem ent and a true value of the m easurand.
Notes:
a.
“Accuracy” is a qualitative concept.
b.
The term precision should not be used for “accuracy”.
Repeatability (of results of measurements)
Closeness of the agreem ent between the results of successive m easurem ents of the sam e m easurand
carried out under the sam e conditions of m easurem ent.
Notes:
a.
These conditions are called repeatability conditions.
b.
Repeatability conditions include:
i.
the sam e m easurem ent procedure
ii.
the sam e observer
iii.
the sam e m easuring instrum ent, used under the sam e conditions
iv.
the sam e location
v.
repetition over a short period of tim e
c.
Repeatability m ay be expressed quantitatively in term s of the dispersion characteristics of the
result.
Reproducibility
Closeness of the agreem ent between the results of m easurem ents of the sam e m easurand carried
out under changed conditions of m easurem ent.
Notes:
a.
A valid statem ent of reproducibility requires specification of the conditions changed.
b.
The changed conditions m ay include:
i.
principle of m easurem ent
ii.
m ethod of m easurem ent
iii.
observer
iv.
m easuring instrum ent
v.
reference standard
vi.
location
vii.
conditions of use
viii.
tim e
c.
Reproducibility m ay be expressed quantitatively in term s of the dispersion characteristics of the
results.
d.
Results are here usually understood to be corrected results.