Table 3.
Variables shown in the BRT analyses to have the greatest influence on the prediction of introduction, naturalization and invasion. The percentage contribution of a variable is based on the number of times the variable is selected for splitting, weighted by the squared improvement to the model as a result of each split and averaged over all trees. For each model, the contribution of the variables is scaled to add up to 100 %, with higher numbers indicating stronger influence on the response.
| Model | Variable | Percentage contribution |
|---|---|---|
| Introduction | Number of native regions | 30.00 |
| Life form | 26.00 | |
| Pollinator type | 17.70 | |
| Species native to Polynesia | 9.90 | |
| Flower sexuality | 8.20 | |
| Habitat | 8.20 | |
| Naturalization | Number of introduced regions | 65.90 |
| Life form | 16.00 | |
| Habitat | 9.80 | |
| Number of uses | 8.30 | |
| Invasion | Life form | 48.90 |
| Number of introduced regions | 35.30 | |
| Pollinator type | 15.90 |