An DOE is a statistical test setup with more factors on different levels combined in one experiment. It is used when analyzing complex problems with a lot of influence factors in once. Instead of testing each factor individually in a DOE more factors are variated at once to reduce the amount of test with the possibility to analyze interactions between factors. This is done by using test arrays. These arrays are full factorial (all combinations are tested) or fractional arrays (a part of a full factorial test setup to reduce the amount of tests).

This document is an introduction of the DOE functionality of Develve for more information how to conduct a DOE see How conduct a DOE.

Select DOE in the statistical mode drop-down menu to start a Design of experiment. The data of the input table is sorted according the factorial table (see example). With this option it is possible to conduct a DOE with various Full factorial array or Fractional arrays.

For calculating the statistical properties of a data set the data must entered in the input table 1. The data will sorted according the Factorial table 9. and the result will be displayed in the result array 3. and Graph image 2.

1. Input table

Input Table for the data to be analyzed. The amount of decimals behind the point can be changed in the box in the upper left corner.

9. Factorial table

Every factor (Columns in the Factorial table) and level (small and big with factor A) are sorted for calculating the influence of every factor and level. See table below.

A

B

C

D

E

F

G

All factors

Size

Size

Weight

Weight

Color

Color

Levels

small

Big

heavy

Light

Dark

white

10

10

10

10

20

20

20

20

30

30

30

30

40

40

40

40

50

50

50

50

60

60

60

60

70

70

70

70

80

80

80

40

Mean

45.00

35.00

55.00

40.00

50.00

45.00

45.00

n

8

4

4

4

4

4

4

Median

45.00

35.00

55.00

40.00

50.00

45.00

45.00

STDEV

24.49

23.80

23.80

25.82

25.82

28.87

23.80

2. Graphs

The graph of the data set is life updated after the data is entered. With the graph selector 7. the type of graph can be chosen. The graph can be made invisible or visible with the selector in the upper left corner Graph. By clicking on a graph a bigger version of the graph will be displayed in a pop-up Except the DOE response graph.

3. Result table

In this table the result will be displayed according the selection in the selection area 8. For comparing data sets put in the comparing column in the first row and this will be used for; t-test, F-test, etc.
Row 2-4 is for the tolerance borders and nominal value, these will be displayed in the graphs and used for; Cp, Cpk and the % out of tolerance calculation.

8. Selection area

In the selection area the calculation to be executed can be selected.