RADIOMETER ABL800 FLEX Reference Manual

ABL800 FLEX Reference Manual 5. Performance characteristics
Definition of terms and test conditions, Continued
Reproducibility
Reproducibility is obtained from repeated measurements within several days using:
• Random instrument
• Random sample
• Random operators.
Reproducibility for each level is pooled for all test instruments and test days.
Total variation
range
The total variation range is given as ±2 × S
X
, where S
X
is the reproducibility.
Imprecision
Repeated measurements using one analyzer on samples assumed to be identical
will not necessarily yield identical results. The degree of variation in the results is
a measure of the precision of the analyzer.
The following table describes the parameters used to characterize precision
obtained via the performance tests on the ABL700 Series of analyzers.
Parameter Description
S
0
Repeatability
This is a standard deviation obtained from repeated
measurements within a short interval of time using:
• The same instrument and location
• The same measurement procedure
• Identical portions of the same sample
• One operator per instrument
S
0
for each level is pooled for all test instruments and test days.
S
D
Day-to-day variation
This is a standard deviation obtained from repeated
measurements over all test days.
Includes contributions from differences in calibration states of the
analyzers throughout the test days.
S
ABL
Uncertainty of bias on a random instrument
S
ABL
is used for repeated determinations on one sample. This
standard deviation includes the inter-instrument variations,
sample variations, and uncertainties from standard solutions and
reference methods.
S
X
Uncertainty of bias on a random instrument for a single
measurement
S
X
is a standard deviation which includes S
ABL
, S
D
and S
0
.
Continued on next page
5-3

RADIOMETER ABL800 FLEX Specifications

General

Brand	RADIOMETER
Model	ABL800 FLEX
Category	Measuring Instruments
Language	English