When a sample or a group of sample samples serves as control baseline in the experiment design, other a baseline control, the experimental samples can be normalized by subtracting or divided dividing by the baseline sample(s), e.g. in PCR data to obtain delta delta CT values. 

The Normalize to baseline option is available in the Normalization and Scaling section of the context-sensitive menu (Figure 1) upon selection of any counts count matrix data node containing matrix of measurements of observations (e.g. samples) on features (e.g genes).

There are three options to choose the baseline samples:

• use all samples
• use a group
• use matched pairs

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