Table 1. Optimized Parameters for Each Algorithm.
| algorithm | optimized parameters | unbalanced TS | equal size models |
|---|---|---|---|
| RF | split criterion | gini index | |
| attribute sampling | square root | ||
| set of attributes for each tree | different | ||
| number of trees | 423 | ||
| tree depth | 6 | ||
| equal size sampling | yes | ||
| kNN | number of neighbors to consider | 5 | 7 |
| weight neighbors by distance | yes | no | |
| GB | number of trees | 280 | 100 |
| learning rate | 0.98 | 1 | |
| attribute sampling | square root | ||
| set of attributes for each tree | same | ||
| maximum tree depth | 8 | ||
| XGB | eta | 0.589 | 0.28 |
| boosting rounds | 253 | 100 | |
| gamma | 0.182 | ||
| lamba | 4.842 | ||
| alpha | 0.211 | ||
| maximum depth | 6 |