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CALCULATION METHOD
MAX-MIN
ΣXi/N
σn = n
((N NΣXi
2
− (ΣXi )
2
) / N
2
)
1/2
σn
-
1 =
((N NΣXi
2
− (ΣXi )
2
) / N N(N−1))
1/2
Number of data to become LSL LXi
Number of data to become LSL lXi
P =
((−NG) + (+NG))/N
C
P =
TOL/(6σN+1)
(TOL:USL+LSL)
C
PK=
Zmin/3
Zmin: ZUSL, ZLSL Smaller value of ZLZL
ZUSL = (USL
-
X) /σn
-
1
ZLSL = (X
-
LSL) /σn
-
1
PRINT MEANING FORMULA
N
MAX
MIN
R
X
σn
σn
-
1
−
NG
+NG
P
CP
CPK
Data count
Maximum value of data
Minimum value of data
Range of data
Mean value of data
Standard deviation
Sample standard deriva-
tion
Amount of data smaller
than lower limit
Amount of data larger than
upper limit
Fraction defective
Process capability index
Process capability index
which considers deviation.
4. Calculation formula
4.1 Calculation of Mode1, Mode2
Table 2 Calculation formula 1