expected value

Discrete Random Variables: For a discrete random variable, the expected value, usually denoted as μ or E(X), is calculated using The formula means that we multiply each value,x, in the support by its respective probability, f(x), and then add them all together. it can be seen as an average value but weighted by the likelihood of the value.

##Example:

x	0	1	2	3	4
f(x)	1/5	1/5	1/5	1/5	1/5

=2

Properties:

Continuous Random Variables: The expected value(or mean) for a continuos random variables , usually denoted as μ or E(X), is calculated using: