Testing commutability of other materials
Test the commutability of reference materials or processed samples with unprocessed samples.
You must fit a Deming regression to perform this task.
- On the Analyse-it ribbon tab, in the Method Comparison group, click Restrict to Group.
- In the Group / Color / Symbol drop-down list, select the variable indicating the type of sample.
- In the Restrict fit to group drop-down list, select the group of unprocessed samples.
- On the Fit Y on X task pane, in the Prediction band edit box, type 95%, and if required select the Familywise coverage check box.
- Click Recalculate.
The scatter plot shows the points in different colors depending on the type of sample. The fit is restricted to a unprocessed samples and the prediction band includes any additional samples that are commutable with the unprocessed samples. A table lists the additional samples and if they are commutable with the unprocessed samples.
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