Hi Jarmo/jthi,
I need one more help on this part.
I would like to have one generic script on the similar lines what you have suggested, but this time, the model driven multivariate control chart should use some benchmark models (either PCA or PLS) to fix the control limit. The reason is, for continued process verification purpose, once we fix the limit (calculated from the historical dataset without any outliers), the future batches have to be monitored against this limit. Currently, what's happening is, every time when this script is run, it generates new control limit (for obvious reasons) as the dataset is differing.
So, the first part is to fix the control limit (all the historical/golden dataset should fall below the control limit) and to do this, is it possible to develop a model with cross-validation to finalize the number of components so that the data-points fall below the control limit (off course, after removing the outliers)? The tricky part here I am facing, even though the so-called outliers are removed, every time the MDMVCC gives one or other data point beyond a control limit (as the dataset is changing). This has to be fixed.
second part is to run this script (with fixed control limit) on the subsequently manufactured batches to identify any excursions in the variables as part of CPV activity.
The overall idea is to have a generic MDMVCC script (from a benchmark model) which can predict/identify the outliers/variations with good accuracy.
Appreciate if you can guide me or throw some more light on this request.
Thanks in advance !!
KR,
Nawaz