topic Re: Curve DoE - defect rate issue? in Discussions

Curve DoE - defect rate issue?

AgnieszkaL — Fri, 17 May 2024 09:29:02 GMT

Hi All

I’ve just started using Curve DoE function and have came across the following challenge:

The defect rate is ~70% - not sure how does this relate to the entire curve? Or just a selected point on the curve? Also, I need max desirability on all response values across the curve concertation range hence the desirability curve is flat – not sure though if that’s OK? Could you comment pls?

Re: Curve DoE - defect rate issue?

Ben_BarrIngh — Mon, 20 May 2024 08:37:15 GMT

The defect rate is based on the simulated values across the whole of the curve, as you have set all of your values as 'Random Normal' -

it may be useful to set your X values for your curve (which looks to be your left most plot) to 'Random Uniform', this way you get provided a defect rate across your whole range. Another option is to keep it 'Fixed' to provide a defect rate for a specific point within the curve.

Re: Curve DoE - defect rate issue?

SamGardner — Mon, 20 May 2024 20:03:55 GMT

The issue here is that the Curve DOE model is predicting the curve, which is shown on the left panel in the profiler.

If the curve value at a given time point is something that you want to achieve or optimize, the best approach would be to fix the X value for the curve (lock it by Cntl-Click on the graph and select the "Lock Factor Setting"). Then do not use a random distribution for inputs for that X factor.

You can use the "Maximize For Each Grid Point" option to sequence the locked factor over 5 steps (from the min to the max of the X in the graph).

Re: Curve DoE - defect rate issue?

AgnieszkaL — Wed, 22 May 2024 14:15:51 GMT

Thanks a lot - that is useful to know!