Notation for difference of two random variables

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Is there any standard notation for the distribution of the difference of two random variables. For the sum of two random variables $X$ and $Y$, we can write,

$f_{X + Y}(t) = (f_X \ast f_Y)(t)$

but I can't seem to find any standard notation for representing the difference.

Edit: To clarify, $X$ and $Y$ are independent continous random variables. I could write out the whole equation,

$f_{X-Y}(t) = \int_{t'} f_X(t') f_Y(t'-t) dt'$

but I was wondering if there is some notation similar to that for convolution where I could just write

$f_{X-Y}(t) = f_X(t) \ast f_Y(-t)$

Note: The $\ast$ symbol is used in the Wikipedia page for convolution here: https://en.wikipedia.org/wiki/Convolution.