它有多少个类别，每个类别多少实例？

DOTA 数据集中一共包含 15 个类别，分别是:

1. Plane
2. Baseball diamond
3. Bridge
4. Ground track field
5. Small vehicle
6. Large vehicle
7. Ship
8. Tennis court
9. Basketball court
10. Storage tank
11. Soccer-ball field
12. Roundabout
13. Harbor
14. Swimming pool
15. Helicopter

每个类别的实例数量如下：

| 类别 | 实例数量 |
|-------------------|---------|
| Plane | 2617 |
| Baseball diamond | 1737 |
| Bridge | 790 |
| Ground track field| 227 |
| Small vehicle | 11828 |
| Large vehicle | 2300 |
| Ship | 965 |
| Tennis court | 532 |
| Basketball court | 779 |
| Storage tank | 1080 |
| Soccer-ball field | 879 |
| Roundabout | 156 |
| Harbor | 210 |
| Swimming pool | 1216 |
| Helicopter | 70 |

总的实例数量是 188,282 个。