| cross_fit_helper | Helper function to for cross-fitting |
| custom_helper | Custom generator |
| double_ML | Post double selection. |
| fit_cross | Cross-fitting helper |
| glmnet_helper | Helper function(glmnet). |
| input_checker | Helper function for input checking |
| nn_helper | Helper function for neural networks fitted by neuralnet |
| ols_helper | Helper function(least squares). |
| plot_ML | Plot the fitted Debiased ML treatment effects. |
| rf_helper | Helper function(randomforest). |