Example

Consider the random experiment of rolling a fair die with four faces (tetrahedron) numbered 1 to 4 and observing the result on the bottom face. The set of possible outcomes is [latex]\textrm{U}[/latex] = {1, 2, 3, 4}. The probability space of this event is:

[latex]\left\{ \left( \left\{ 1\right\} ,\dfrac {1} {4}\right), \space \left( \left\{ 2\right\} ,\dfrac {1} {4}\right), \space \left( \left\{ 3\right\} ,\dfrac {1} {4}\right), \space \left( \left\{ 4\right\} ,\dfrac {1} {4}\right) \right\} [/latex]