Stochastic variable and Variable quantity

Stochastic variable noun - A variable quantity that is random.

Variable quantity and stochastic variable are semantically related. In some cases you can use "Variable quantity" instead a noun phrase "Stochastic variable".

Variable quantity noun - A quantity that can assume any of a set of values.

Stochastic variable and variable quantity are semantically related. Sometimes you can replace phrase "Stochastic variable" with "Variable quantity", this phrases are similar.