Applying a Model Quick Start
Previous Topic: Review Results
Congratulations! You have collected calibration data and gone through the exercise of building a model that meets your objectives. Now, you want to exert one of the most stringent tests - applying your model to new data. If you have just completed the model building process, all that needs to be done is to load some new data as validation data. Another scenario is that you have a model that has been built awhile ago, and you wish to apply it to some new data.
In this example (using the included demonstration dataset "nir_data") , there are three variables in the workspace
The concentration data contains values for five separate components. The model pls_model... predicts only one of these concentration values.
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Now that the model has been loaded
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When you click on the "Review Scores" button, a multiplot figure will open. Try double-clicking on each subplot to create separate figures. One useful plot is Q residuals versus Hotelling's T2, with both the validation and calibration data visible. In the Plot Controls window, select "Hotelling T^2" for the x-axis, and "Q Residuals" for the y-axis. Make sure that the "Show Cal Data with Test" box is checked toward the bottom of the Plot Controls window. Finally, select "View" under the Plot Controls menu, then "Classes", followed by "Cal/Test Samples"; this will apply color/symbol coding for the two classes of samples. It is sometimes useful to use log scales for Q residuals and/or T2; in this example, a log scale is used for the Q residuals. For the second plot, "Y Predicted" is selected for the y-axis along with "Y Measured" for the x-axis. As in the Q residuals vs. T2 plot, the black circles represent the calibration samples and the red triangles denote the validation samples. We note from these two plots that:
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