Conditional Distributions

Conditional mass function

$\Bbb{P}(X = x | Y = y) = \dfrac{\Bbb{P}(X = x, Y = y)}{\Bbb{P}(Y = y)}$

$\Bbb{P}(X = x, Y = y) = \Bbb{P}(X = x | Y = y) \Bbb{P}(Y = y)$

Conditional density