$\mathbf{a}$	Sum vectored, zero mean acceleration signal vector
${\mathbf{a}}^{\prime }$	Sum vectored, acceleration signal vector
${\mathbf{a}}_{\mathbf{x}}$	Acceleration signal vector along x-axis
${\mathbf{a}}_{\mathbf{y}}$	Acceleration signal vector along y-axis
${\mathbf{a}}_{\mathbf{z}}$	Acceleration signal vector along z-axis
$a(n)$	Acceleration signal at sample n
${\mathcal{A}}_i$	Wavelet approximation coefficients at level i
$\beta$	Signal spectral exponent
d	Fractional difference parameter
$\tilde{d}$	Fractional integration coefficient
$d_c$	Drift constant in stationary test
${\mathcal{D}}_i$	Wavelet detail coefficients at level i
$e(n)$	Innovation process in stationary test
$ϵ(n)$	Random variable
$f_s$	Sampling frequency
$fd$	Fractal dimension
$\gamma$	Autoregressive coefficient with value < 1
$\Gamma$	Gamma Function
H	Hurst exponent
$H_0$	Null hypothesis in stationary test
$H_1$	Alternative hypothesis in stationary test
i	Wavelet transform level
$I(d)$	Integrated part of ARIMA/ARFIMA model
k	Shift/translation index
$\mathbb{L}$	Lag operator
$\lambda$	Deterministic trend with coefficient
${\mu }_a$	Mean of sum vectored, zero mean acceleration signal vector
${\mu }_{a^{\prime }}$	Mean of sum vectored acceleration signal vector
${\mu }_{D_i}$	Mean of wavelet detail coefficients at level i
${\mu }_s$	Mean of accelerometer first order difference signal
n	Signal sample number
N	Total number of samples
$\omega$	Angular frequency
$p-value$	Confidence value for unit root tests
$p_{max,ADF}$	Maximum delay value for ADF test
$p_{max,KPSS}$	Maximum delay value for KPSS test
${\varphi }_{i,k}(n)$	Scaling wavelet function with shift index k, at level i
${\psi }_{i,k}(n)$	Mother wavelet function with shift index k, at level i
q	Number of random perturbations
r	Number of autoregressive terms
$s(n)$	First order difference, accelerometer signal
$S(\omega )$	Power spectrum density
${\sigma }_a^2$	Variance of sum vectored, zero mean acceleration signal vector
${\sigma }_{a^{\prime }}^2$	Variance of sum vectored acceleration signal vector
${\sigma }_{D_i}^2$	Variance of wavelet detail coefficients at level i
${\theta }_p$	General moving average coefficients
$v_1(n)$	Stationary process
$v_2(n)$	Independent and identically distributed process with 0 mean
${\zeta }_r$	General autoregressive coefficients