Re-generating a fractional factorial design resolution IV or lower may give wrong design (Q30)

Symptoms:

If you generate a fractional factorial design of resolution IV or lower and then change your mind, and go to Design | Objective, select RSM and generate a CCC or CCF design, the generated RSM design is incorrect.

Cause:

This is due to the fact that MODDE^® does not delete the initial fractional factorial design but updates it incorrectly.

Workaround:

Copy the factors in a new investigation and then generate the CCC or CCF design.

Status:

Fixed in the next release.

More Information:

If you generate a fractional factorial design of resolution IV or lower and then change your mind, and go to objective, select RSM and generate a CCC or CCF design, the generated RSM design is incorrect.