Index: The Book of Statistical ProofsGeneral Theorems ▷ Probability theory ▷ Random variables ▷ Constant

Definition: A constant is a quantity which does not change and thus always has the same value. From a statistical perspective, a constant is a random variable which is equal to its expected value

\[\label{eq:EX} X = \mathrm{E}(X)\]

or equivalently, whose variance is zero

\[\label{eq:VarX} \mathrm{Var}(X) = 0 \; .\]
 
Sources:

Metadata: ID: D96 | shortcut: const | author: JoramSoch | date: 2020-09-09, 01:30.