题目
If a random variable X has density f(x) and random variable Y has density g(y), then X and Y are independent of each other if and only if their joint density function h(x, y) satisfies:
选项
A.h(x, y) = kf(x)g(y); k \u2260 1
B.h(x, y) > f(x)g(y)
C.h(x, y) = f(x)g(y)
D.h(x, y) < f(x)g(y)
答案
C
解析
解析C is the definition of independence between two random variables. Two random variables X and Y are independent if and only if their joint density function is the product of the two marginal density functions.