[MADLIB-925] Improve RF output format for variable importance (and new DT/RF impurity importance)

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: v1.15
• Component/s: Module: Random Forest
• Labels: starter
• Assignee: Nandish Jayaram
• Reporter: Frank McQuillan
• Created: 16/Nov/15 21:26
• Updated: 01/Aug/18 22:31
• Resolved: 01/Aug/18 20:06

Description

As a user,
I want to have an easier way of accessing the variable importance output from random forest so that I can understand which are the most important variables.

Current method of getting variable importance for each variable (in a tabular format - assuming output table name is `rf_output`):
```
SELECT unnest(regexp_split_to_array(cat_features, ',')) as variable,
unnest(cat_var_importance) as importance
FROM rf_output_group, rf_output_summary;
```

This is a cumbersome query to write and has to be written twice - for categorical and for continuous features.

Issue Links

• links to: GitHub Pull Request #295
• mentioned in: Page Loading...