Table 1.
Summary of Modeling Algorithms Used in This Study
| Model | Synonym | Model Category | Tuning Parameters |
|---|---|---|---|
| Machine Learning Algorithms | |||
| Linear regression | Linear | Simple model | Alpha, Lambda |
| k-nearest neighbors | KNN | Simple model | K |
| Random Forest | RF | Ensemble model | mtry |
| Bagged Model | Bag | Ensemble model | Nonea |
| Stochastic Gradient Boosting | Gbm | Ensemble model | n.trees; shrinkage, n.minobsinnode |
| Support vector machine | SVM | Support vector machine | C |
| Least-squares SVM | LS-SVM | Support vector machine | Cost, loss |
| L2-Regularized SVM | L2-SVM | Support vector machine | Cost, loss |
| Deep Learning Algorithm | |||
| Deep neural networks | DNN | Neural networks | Rate, L1, L2 |
Notes: Alpha, Lambda: the penalty parameters in the elastic regression model. C: A regularization parameter that controls the trade-off between the misclassification and width of the margin. Cost: The cost function in Least-squares or L2-Regularized SVM model. Loss: The Loss function in Least-squares or L2-Regularized SVM model. K: A parameter in KNN model that refers to the number of nearest neighbors. mtry: Number of variables randomly sampled as candidates at each decision tree. n.trees: Number of decision trees in the stochastic gradient boosting model. n.minobsinnode: Minimum number of samples in tree terminal nodes. L1: a loss function to minimize the error which is the sum of all the absolute differences between the measured values and predicted values. L2: a loss function to minimize the error which is the sum of all the squared differences between the measured values and predicted values. Rate: The learning rate in deep learning model that controls how much to change the model in response to the estimated error when model weights are updated for each of the iterations. shrinkage: The learning rate in the stochastic gradient boosting model. aNone of the parameters were tuned in this model.