Being careful about the handling of scale, intercepts, and penalties, verify that our function casl_lm_ridge produces similar results to MASS::lm.ridge and glmnet::glmnet for specific values of λ Now,...

Being careful about the handling of scale, intercepts, and penalties, verify that our function casl_lm_ridge produces similar results to MASS::lm.ridge and glmnet::glmnet for specific values of λ

Now, add additional input parameters to ridge_reg for the validation data: X_valid and y_valid. If supplied, return only the best value of β.