备考FRM考试中,考生有很多的事项需要注意的,另外做大量的真题解析也是很重要的,下文是融跃小编列举的FRM错题解析,备考生必看!


Regarding white noise, each of the following statements is true except?

A.If a process is zero-mean white noise, then is must be Gaussian white noise.

B.If a process is Gaussian (aka, normal) white noise, then it must be (zero-mean) white noise.

C.If a process is Gaussian (aka, normal) white noise, then it must be independent white noise.

D.If a process is stationary, has zero mean, has constant variance and it serially uncorrelated, then the process is white noise.

答案:A

解析:First,zero-mean white noise maybe uncorrelated but not necessarily serially independent (the difference between or crelation and independence Second,white noise(aka,zero-mean white noise))is not necessarily normally distributed.If the white noise is serially independent and normally distributed,we call it a Gaussian white noise.

关联考点:白噪音种类之间的区别

易错点分析:容易把白噪音当作是独立的、服从正态分布的,白噪音、独立白噪音、高斯白噪音之间的关系搞不清楚。首先明白白噪音的三个条件(1.均值为0;2.方差为常数;3.残差项序列不相关)。三者正确的关系应该是:白噪音(一定是零均值)+独立条件=独立白噪音;白噪音(一定是零均值)+服从正态分布=高斯白噪音。