While working on a data set, how do you select important variables? Explain your methods.

While working on a data set, how do you select important variables? Explain your methods.





Answer: Following are the methods of variable selection you can use:


  • Remove the correlated variables prior to selecting important variables
  • Use linear regression and select variables based on p values
  • Use Forward Selection, Backward Selection, Stepwise Selection
  • Use Random Forest, Xgboost and plot variable importance chart
  • Use Lasso Regression
  • Measure information gain for the available set of features and select top n features accordingly.

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