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Graphical Methods in
CAPA
G1: Histogram, Gauss curve, average(the middle yellow vertical line),
(xbar-3s, xbar+3s) (the left and right yellow vertical line), tolerances LSL, USL (the left and
right vertical full red line), target value T (the middle vertical full red line).
G2: Q-Q graph: Quantiles of distribution N(0,1) on the horizontal
axis, order statistics x(i) on the vertical axis. Tolerances: LSL=horizontal bottom
red line, USL=horizontal top red line. If the points lie between the LSL and USL and
"close to" the line, then the data are in the tolerance and have normal
distribution.
G3: Multivariate characteristic of capability
White rectangle=tolerance area, i.e. an area of the prescribed location of quality
characteristics. Ellipse with red points = area of the quality characteristics real
location. The yellow cross passes through the means of the quality characteristics
(the center of the ellipse), the white cross passes through the target values of the
quality characteristics and defining the center point (T1,...,Tk).
G4: Outliers (Grubbs' test graphically)
Vertical yellow lines = borders whose crossing/exceeding signals that the value (which
crossed it) is an outlier (and thus a reason to be excluded). A random number
is assigned to each x as its y-coordinate. The data is then spread around the
x-axis to prevent merging when large amounts of data are to be evaluated.
G5: Castagliola's method
It shows the point of an empirical distribution function and its color approximation with
polygons of different degrees. The found empirical distribution function is used in
the numeric section of the program for an estimation of the index CpK for any type of
distribution.
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