Moment coefficient of skewness for ungrouped data
Let $x_1, x_2,\cdots, x_n$
be $n$ observations. The mean of $X$ is denoted by $\overline{x}$ and is given by
$$ \begin{eqnarray*} \overline{x}& =\frac{1}{n}\sum_{i=1}^{n}x_i \end{eqnarray*} $$
Formula
The moment coefficient of skewness $\beta_1$ is defined as
$\beta_1=\dfrac{m_3^2}{m_2^3}$
The moment coefficient of skewness $\gamma_1$ is defined as
$\gamma_1=\sqrt{\beta_1}=\dfrac{m_3}{m_2^{3/2}}$
where
$n$
total number of observations$\overline{x}$
sample mean$m_2 =\frac{1}{n}\sum_{i=1}^n (x_i-\overline{x})^2$
is second central moment$m_3 =\frac{1}{n}\sum_{i=1}^n (x_i-\overline{x})^3$
is third central moment