Mathematical Notation

Probability and Statistics

Symbol	Formula	Explained
\(\mu\)	\(\sum_{x} k P(X=x) = \int_{-\infty}^{\infty} x f(x) d x\)	🔗
\(V(X)\) or \(\sigma^2\)	\(E[(X - E[X])^2] = E[(X - \mu)^2] = E[X^2] - E[X]^2\)	🔗
\(\sigma\)	\(\sqrt{V(X)}\)	Standard deviation
\(Cov(X,Y)\)	Covariance of X and Y	Covariance of X and Y
\(\bar{X}\)	The sample	The sample mean is an average value