31. Fill in the blank: A random forest model grows trees by taking a random subset of the available features in the training data, then _____ each node at the best feature available to that tree.
- bagging
- tuning
- bootstrapping
- splitting
32. Which of the following statements correctly describe gradient boosting? Select all that apply.
- Each base learner in the sequence is built to predict the residual errors of the model that preceded it.
- Gradient boosting machines have difficulty with extrapolation.
- Gradient boosting models can be trained in parallel.
- Gradient boosting machines can be difficult to interpret.
33. Fill in the blank: In tree-based learning, the decision tree’s _____ represent where the first decision is made.
- roots
- branches
- leaves
- splits
34. Fill in the blank: A random forest is an ensemble of decision-tree _____ that are trained on bootstrapped data.
- observations
- variables
- statements
- base learners
35. What are some benefits of boosting? Select all that apply.
- Boosting scales well to very large datasets.
- Boosting can handle both numeric and categorical features.
- Boosting algorithms are easy to understand.
- Boosting does not require the data to be scaled.
36. Which of the following statements correctly describe gradient boosting? Select all that apply.
- Gradient boosting machines cannot handle messy data.
- Gradient boosting machines do not have coefficients or directionality.
- Gradient boosting machines are often called black-box models because their predictions cannot be explained easily.
- Gradient boosting machines have a lot of hyperparameters.