Select an alternative model from Discover Key Predictors with TreeNet® Classification

Run Predictive Analytics Module > TreeNet® Classification > Discover Key Predictors. Click the Select an Alternative Model button after the Predictor Elimination table.
Note

This command is available with the Predictive Analytics Module. Click here for more information about how to activate the module.

Overview

When you use Discover Key Predictors to remove the least important predictors, Minitab Statistical Software produces results for the model with the best value of the accuracy criterion for the analysis, such as the minimum average –loglikelihood. Minitab lets you explore other models from the sequence that led to the identification of the optimal model. Generally, you select an alternative model if another model has a value of the criterion close to the best, but with fewer predictors. A model with fewer predictors is easier to interpret, can have better prediction accuracy, and allows you work with a smaller number of predictors.

For example, the following model selection table has 13 steps. The model with the least average –loglikelihood is the model with all of the predictors. The model at step 11 has an average –loglikelihood that is relatively close to the best value. The model at step 11 has 3 predictors. The full results from the model at step 11 are also of interest.

Model Selection by Eliminating Unimportant Predictors

Test
ModelOptimal
Number
of Trees
Average
-Loglikelihood
Number of
Predictors
Eliminated Predictors
12680.27393629None
22680.27418627Foam Stability, Bulk Density
32340.27384326Least Gelation Concentration
42330.27435025Oven Mode 2
52320.27494324Kiln Method
62730.27555323Oven Mode 1
72440.27481122Mix Speed
82680.27425821Oven Mode 3
92720.27418520Resting Surface
102320.27407719Bake Temperature 3
112870.27359818Mix Tool
122270.27435817Bake Temperature 1
132760.27537416Rest Time
142720.27608215Water
152680.27559514Caustic Concentration
162680.27781013Swelling Capacity
172530.27643612Emulsion Stability
182310.27615911Emulsion Activity
192680.27353710Water Absorption Capacity
202600.2734559Oil Absorption Capacity
212990.2728488Flour Protein
222780.2726297Foam Capacity
23*2990.2671846Flour Size
242970.2886215Bake Temperature 2
252340.3303424Dry Time
262900.3059933Gelatinization Temperature
272450.5343452Bake Time
281460.5998371Kiln Temperature
The algorithm removed one predictor and any predictors with 0 importance at each step.
* Selected model has minimum average -loglikelihood. Output for the selected model follows.

Perform the analysis

Click Select an Alternative Model in the output. A dialog box opens that shows a plot of the criterion against the number of eliminated predictors and a table that summarizes the steps.

Compare the criteria

To select an alterative model, click a point on the graph or a row in the table. Press Display Results to create the results for that model.

Once you display the results, you can click a button in the output to tune the hyperparameters of the model or to make predictions from the model. For more information, go to Select hyperparameter values to evaluate from the results for TreeNet® Classification or Predict new results for Fit Model and Discover Key Predictors with TreeNet® Classification.

Tip

To compare the output of two different analyses or reports, right-click the second item in the Navigator and choose Open in Split View.