Table 2.

Summary of the data representations used in the current study.

Data Representation	Number of Features per Signal	Description of the Features
Mazilu [44]	7	Mean, standard deviation, variance, frequency, entropy, energy, freeze index (power of the freezing band 3–8 Hz divided by power in locomotor band 0.5–3 Hz), and the sum of freeze index and locomotion band.
MFCCS [52]	12	Mel frequency cepstral coefficients adapted to inertial signals.
FFT [53]	64	Symmetric part of FFT N = 128
FFT + one previous window	128	Symmetric part of FFT N = 128, plus 1 previous spectral window.
FFT + two previous windows	192	3 × Symmetric part of FFT N = 128, plus 2 previous spectral windows.
FFT + three previous windows	256	4 × Symmetric part of FFT N = 128, plus 3 previous spectral windows.