# Functions of random variable and their expected value

1. Apr 16, 2010

suppose we have random variable defined a function of another random variable such that $$Y = \mathbb{E}(X)$$
it seem then $$Y$$ is a constant. then $$\mathbb{E}(Y) = \mathbb{E}(X)$$ does this even make sense ?

2. Apr 17, 2010

### mathman

If Y=E(X), then it is constant. Calling Y a random variable doesn't make sense. What is the context?