FAQ - Frequently Asked Questions
Issue:
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What is PLS1 vs PLS2 and how do I create separate PLS1 models when I have a multi-column y-block?
Possible Solutions:
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If your y-block contains multiple y-columns, PLS always performs a PLS2. This creates a single model where all y-columns contribute to the loadings of the model. This can sometimes improve performance of the model, particularly when the signal in the different y-columns is correlated but the noise is not. A PLS1 model is a model built on a single y-column and the model reflects only covariance between the X block and that single y-column.
If you want separate PLS1 models for each y-block column, you have to exclude all but one of your y-columns and build independent models. To choose y-columns to use, see the Edit/Select Y-Columns menu item in the Analysis GUI or, from the command line, use the y-block's include{2} field. The resulting PLS model will be built for only the included columns.
This distinction is necessary because each PLS1 model contains a different set of loadings, Q, T2, and limits and an individual model can contain only one set of these.
Still having problems? Check our documentation Wiki or try writing our helpdesk at helpdesk@eigenvector.com
