E over X => Expected Value

Question

I stumbled upon this formula while reading about supervised machine learning. I am wondering what the E over X means.

Does the E over X basically just mean the expected value of the random variable X? (=> E(X)) Or does it have a different meaning

Thank you very much

Answer 1

$\mathbb{E}$ symbol is usually used for expectation values. It means you are calculating the expected value with respect to the subscript variable

$$\mathbb{E}_X\rho(x, y) = \int x \rho(x,y)dx$$