Card Set Information
What is a Youden Plot?
graphical technique to determine within-lab and between lab variability.
How many standard deviations are drawn around the origin of a youden plot?
How many samples are each lab given?
2 - ea w similar but not equal conc of analytes. first result is (x) and second is (y)
the 45 degree reference line is drawn to measure...?
systematic and random error
distance of ea point from the origin. values that accumulate in upper right or lower left
distance of ea point from the line at 45 degrees to the origin. distributed around the mean.
is random or systematic error used to calculate the radius of the circle?
To avoid errors when making a Youden plot...?
-use same matrix
-similar std dev. and conc.
-same level of precision
What is a Shewhart Chart?
graphical analysis of variance (ANOVA)
- determine acceptable levels of quality
- achieve these levels & maintain performance
what % of values should lie inbetween the follwing deviations, respectively. mean - 1, 2-3, near control limits
mean - 1; 68%
2 - 3; 28%
near control limits 2%
The shewhart chart is evaluated on the basis of...?
Spread - inspect R chart to obs process varia
Position - data pts equally distributed around mean, should not exceed control limits
variability is dependent on?
- # of samples
- frequency of samples
- size of sample
degradation of sorbent in GC would be special or common cause?