statistics

Common symbols:

$\mu$ : mean

$\bar{x}$ : mean for a sample

$\sigma$ : standard deviation

$s$ : sample standard deviation

$s^2$ or ${\sigma }^2$ : sample or population variance

$p$ : probability

$\hat{p}$ : probability from a sample

$X\sim N$ : means “x distributed over Normal”, meaning it’s using the Normal Distribution.

$\bar{X}$ : sample mean

$N$ : The number of scores in a study

$n$ : The number of scores in a sample ($n=N$ when in a single-sample test).

$D$ : Difference between scores (e.g. in a related-samples t-test

$\bar{D}$ or ${\mu }_D$ : average differences in the samples or population respectively.

$\Sigma D$ : Sum of score differences