Table 4.

Employed preprocessing and feature extraction approaches for gender (G) classification and age (Ag) prediction. ‘*’ denotes that all of their algorithms used the approach. Numbers represent the algorithm numbers (i.e., instead of ‘Alg.1’, ‘Alg.2’—we mention ‘1’, ‘2’).

Preprocessing									Feature
Team No.	Gender (G)/Age (Ag)	Windowing	Signal Normalization	Coordinate Transformation	Low-Variance Data Removal	PCA Matrix Calculation	Gyroscope Exclusion	Z-Score Standardization	HMM-UBM	Raw Data	Fourier Transform	Gait Cycle Calculation	Gait Dynamic Image (GDI)	Angle Embedded GDI	Statistical Features Extraction	Eigen Projection Matrix	Ensemble of Previous Methods
T1	G										1
.	Ag
T2	G	*													*
.	Ag	*													*
T3	G	*	*	*						*		*					4
.	Ag	*	*	*						*		*					5–7
T4	G									1
.	Ag									1
T5	G	*			2–4			*
.	Ag	*			2–4			*									3, 4
T6	G	*		*										*
.	Ag	*		*										*
T7	G			2–5			1		2	3	2		2	6		2	7
.	Ag			2–5			1		2	3	2		2	6		2	7
T8	G			*		*						*
.	Ag			*		*						*
T9	G	1, 3	3							2		3			1, 3
.	Ag	1, 3	3							2		3			1, 3
T10	G	*													*
.	Ag	*													*