某一分类结果的kappa系数大于0.8时，说明分类精度非常好。

单项选择题The author may agree with all the following statements EXCEPT ____. A、Failure often serves as a reminder for many people to carry on. B、Some artists become slaves of fame due to public demands. C、People want fame even though it has a negative side. D、Some people want to gain fame in order to demonstrate they are better than their friends expected.

单项选择题移动减速信号牌的含义是（） A、要求列车紧急停车的信号 B、要求列车降低到要求的速度。 C、在不需要停车信号或减速信号防护的一般维修作业中，使用作业标防护 D、要求按规定速度运行