Table 4.

Assumed equations for the Time-domain features.

Time-Domain feature	Equation
Maximum	max − val = max(x)
Mean	$\overline{x}=\frac{1}{N_w}·\sum _{i=1}^{N_w}{x}_i$
MAD	$MAD=\frac{1}{N_w}\sum _{i=1}^{N_w}|x_i-\overline{x}|$
Variance	$var=\frac{1}{N_w}\sum _{i=1}^{N_w}{(x_i-\overline{x})}^2$
Skewness	$g_m=\frac{1}{{N_w·s}^3}\sum _{i=1}^{N_w}{(x_i-\overline{x})}^3$
Kurtosis	$w=\frac{1}{{N_w·s}^4}\sum _{i=1}^{N_w}{(x_i-\overline{x})}^4$
Line Length	$LL=\sum _{k=2}^{N_w}|x_k-x_{k-1}|$
Entropy	$H=-{\displaystyle {\sum }_i{p}_i·lo{g}_2(p_i)}$