The HPREDUCE Procedure

Supervised Variable Selection with HPREDUCE Procedure

The following statements use PROC HPREDUCE for supervised variable selection. The statements specify that y is the response variable, the technique used for variable selection is discriminant analysis, and the maximum number of variables to select is 5.

 proc hpreduce data=getstarted technique=DiscriminantAnalysis;
     class C y;
     reduce supervised y = C x1-x10 / maxeffects=5;
     performance details;
 run;

The output from this analysis is presented in Figure 7 through Figure 11.

Figure 7 shows the "Performance Information" table, which indicates that the procedure ran locally and that four threads were used.

Figure 7: Performance Information

The HPREDUCE Procedure

Performance Information
Execution ModeSingle-Machine
Number of Threads16


Figure 8 displays the "Model Information" and "Number of Observations" tables. The "Model Information" table shows that HPREDUCE procedure performed supervised variable selection. The CLASS variables are parameterized in the general linear model (GLM) parameterization, which is the default. The total number of variables is 12. The technique used for variable selection is discriminant analysis, and the maximum number of variables to select is 5. The "Number of Observations" table shows that all 100 observations in the data set are used in the analysis.

Figure 8: Model Information and Number of Observations

Model Information
Data SourceGETSTARTED
Model TypeSupervised
Class ParameterizationGLM
Selection TechniqueDiscriminant Analysis
Number of Variables12
Number of Variables to Select5

Number of Observations Read100
Number of Observations Used100


Figure 9 shows the "Class Level Information" table, which indicates that the CLASS variable C has 10 unique formatted levels and the CLASS variable y has two levels.

Figure 9: Class Level Information and Response Profile

Class Level Information
ClassLevelsValues
C10A B C D E F G H I J
y20 1


Figure 10 shows the "Selection Summary" and "Selected Variable" tables. The "Selection Summary" table shows which variable (or level for CLASS variables) is selected in each step, in addition to the total variance that is explained by the variables selected so far. The "Selected Variable" table presents all the selected variables and their corresponding variable types.

Figure 10: Selection Summary and Selected Variable

Selection Summary
IterationSelected
Effect
LevelProportion
of
Variance
Explained
SSEMSEAICAICCBIC
1CJ0.08110.91890.009280.01542.0196-0.0385
2x8-0.13230.86770.00885-0.00192.0055-0.0498
3x2-0.16870.83130.00857-0.00482.0067-0.0467
4CC0.19920.80080.00834-0.00212.0145-0.0379
5x4-0.21840.78160.008230.01362.0362-0.0161
6x9-0.23690.76310.008120.02972.05930.0060

Selected Variables
NumberSelected
Variable
Variable
Type
1CCLASS
2x8INTERVAL
3x2INTERVAL
4x4INTERVAL
5x9INTERVAL


Figure 11 shows the "Procedure Task Timing" table, which provides details about how much time is used by each processing step.

Figure 11: Procedure Task Timing

Procedure Task Timing
TaskSecondsPercent
Data Read and Variable levelization0.0415.56%
Effect Levelization0.000.27%
Data Preparation for Discriminant Analysis0.000.00%
Cross-product Accumulation0.1773.05%
Variable Selection0.0311.12%


Last updated: May 25, 2022