ST2515 Operation Manual
16
3.4.3
Parameters of Statistic Analysis
1)
X
: Average value. Corresponding formula:
x
x
n
2)
: Population Standard Deviation. Corresponding formula:
2
2
x
nx
n
(=
n
)
3)
s
: Sample Standard Deviation. Corresponding formula:
2
2
1
x
nx
s
n
(=
1
n
)
4)
p
C
: Process Capability Index (Dispersion). Corresponding formula:
|
|
6
p
Hi
Lo
C
s
5)
p
C K
:
Process
Capability
Index
(Deviation).
Corresponding
formula:
|
|
|
2 |
6
p
Hi
Lo
Hi
Lo
x
C K
s
---------------------------------------------------------------------------------------------------------------------------------
NOTE: Explanations for variables in formulas from 1) to 5)
n
: The total measurement times that a sample is used to make statistic analysis, which
corresponds to the value of TIMES.
x
: Measurement results of each sample measurement. The data are saved in the
instrument buffer memory.
Hi
: Upper limit value, used to be compared, corresponds to the value of UPPER limit.
Lo
: Lower limit value, used to be compared, corresponds to the value of LOWER limit.
When
C
p
, C
p
K
> 1.33, the working capacity is ideal.
When 1.33
C
p
, C
p
K
> 1.00 , the working capacity is qualified.
When 1.00
C
p
, C
p
K
, the working capacity is insufficient.
---------------------------------------------------------------------------------------------------------------------------------
6)
Hi (num): Be used to add up times that the measurement result exceeds the upper limit
value.
7)
Lo (num): Be used to add up times that the measurement result is less than the lower
limit value.
8)
In (num): Be used to add up times that the measurement result passes.
9)
Max: Be used to display the maximum measurement result among all measurement
results.
10)
MaxIndex: Be used to display the test serial corresponding to the maximum
measurement result.
11)
Min: Be used to display the minimum measurement result among all measurement
results.
12)
MinIndex: Be used to display the test serial corresponding to the minimum
measurement result.
