HP 9g Graphing manual Process Capability

7.Press [ ] [ ] [ ] or [ ] to scroll through the statistical variables until you reach the variable you are interested in (see table below).

VariableMeaning

nNumber of x values or x–y pairs entered.

or Mean of the x values or y values.

Xmax or Ymax Maximum of the x values or y values.

Xmin or Ymin	Minimum of the x values or y values.
Sx or Sy	Sample standard deviation of the x values or y values.
σx orσy	Population standard deviation of the x values or y
	values.
Σx or Σy	Sum of all x values or y values.
Σx 2 or Σy 2	Sum of all x 2 values or y 2 values.
Σx y	Sum of (x × y) for all x–y pairs.
CV x or CV y	Coefficient of variation for all x values or y values.

R x or R y Range of the x values or y values.

8.To draw 1-VAR statistical graphs, press [ Graph ] on the STATVAR menu. There are three types of graph in 1-VAR mode: N-DIST (Normal distribution), HIST (Histogram), SPC (Statistical Process Control). Select

the desired graph type and press []. If you do not set display ranges, the graph will be produced with optimum ranges. To draw a scatter graph based on 2-VAR datasets, press [ Graph ] on the STATVAR menu.

9.To return to the STATVAR menu, press [ 2nd ] [ STATVAR ].

Process Capability

(See Examples 43 and 44.)

1.Press [ DATA ], select LIMIT from the menu and press [].

2.Enter a lower spec. limit value ( X LSL or Y LSL ), then press [ ].

3.Enter a upper spec. limit value ( X USL or Y USL), then press [] .

4.Select DATA-INPUT mode and enter the datasets.

5.Press [ 2nd ] [ STATVAR ] and press [ ] [ ] [ ] [ ] to scroll through the statistical results until you find the process capability variable you are interested in (see table below).

VariableMeaning

Cax or Cay Capability accuracy of the x values or y values

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