Processing kodak motion picture films, module 3 analytical procedures

POTENTIOMETRIC TITRATION STATISTICS
Repeatability Standard Deviation, 1s r and
95 Percent Confidence Estimate
Repeatability Standard Deviation is an estimate of the
variability one trained analyst should be able to obtain under
favorable conditions (analyzing a sample, with one
instrument, within one day).
The 95 percent Confidence Estimate (calculated using the
repeatability standard deviation) around a single test will
include the mean value 95 percent of the time.
Samples
(Process
ECP-2 Dev)
“Fresh” at
“Aim”
(2.959 g/L
CD-2)
“Seasoned”,
As
Received
“Seasoned”
with
Standard
Addition
CD-2 (Potentiometrically)
Mean
Level
(g/L CD-2)
(N)
Repeatability
Standard
Deviation,
1S r (g/L CD-2)
95 Percent
Confidence
Estimate
(g/L CD-2)
2.8802 5 0.020 ± 0.056
1.0537 5 0.026 ± 0.072
2.0451 5 0.004 ± 0.011
Bias
Bias is a statistically significant deviation from the known
mix level at a 95 percent confidence level. It is determined
for “fresh” samples only. Bias is not determined for
“seasoned” samples, since the component concentration
level was not determined independent of the test method.
A statistically significant low bias (of 2.6 percent) for
CD-2 was found for a “fresh” tank Process ECP-2 developer
sample. However, the bias for was judged not to be
practically significant.
Recovery
Recovery is used instead of bias for “seasoned” samples,
since the component concentration level was not determined
independently of the test method. It is defined as the
calculated mean for the “seasoned” sample with a standard
addition of the component minus the mean for the
“seasoned” sample, divided by the actual amount of the
standard addition. It is expressed as a percentage. The
recovery of 97 percent is statistically different from 100
percent. However, this was judged not to be practically
significant.
Reproducibility
(Customer) Standard Deviation, 1s c & 95 Percent
Confidence Estimate (not including bias)
The customer standard deviation (1s c ) is an estimate of the
variability a customer could expect when submitting a
sample to any Photoprocessing Quality Services laboratory,
where any trained analyst could test the sample using any
instrument on any day.
The 95 percent confidence estimate (calculated using the
customer standard deviation) around a single test result will
include the mean value 95 percent of the time.
Samples
(Process
ECP-2 Dev)
“Fresh” at
“Aim”
(2.9620 g/L
CD-2)
“Seasoned”,
As
Received
“Seasoned”
with
Standard
Addition
CD-2 (Potentiometrically)
Mean
Level
(g/L CD-2)
2 Processing KODAK Motion Picture Films, Module 3, Analytical Procedures H24.03
(N)
Reproducibility
Standard
Deviation, 1S c
(g/L CD-2)
95 Percent
Confidence
Estimate
(g/L CD-2)
2.8299 16 0.040 ± 0.086
2.5321 16 0.033 ± 0.071
3.3449 16 0.036 ± 0.077