. 2021 Jan 26;21(3):798. doi: 10.3390/s21030798

Table 4.

The highest ranked (first to sixth) selected features using SFFS based on random forest method.

Feature Set	#1	#2	#3	#4	#5	#6
All	max_gyr $_{z}$	sd_acc $_{z}$	mean_gyro $_{z}$	p75_gyr $_{z}$	fft $_{1}$ _acc $_{x}$	max_acc $_{x}$
	(LH)	(sacrum)	(sacrum)	(LF)	(withers)	(sacrum)
Limbs	max_gyr $_{z}$	p75_gyr $_{z}$	p25_gyr $_{z}$	min_gyr $_{z}$	p75_gyr $_{z}$	p25_gyr $_{z}$
	(LH)	(LF)	(LH)	(RH)	(RH)	(RF)
Sac/Wth	sd_acc $_{z}$	sd_acc $_{z}$	ent_gyr $_{z}$	p75_acc $_{x}$	ent_acc $_{z}$	skw_acc $_{z}$
	(withers)	(sacrum)	(sacrum)	(withers)	(sacrum)	(sacrum)
Sac/RF	p25_gyr $_{z}$	sd_acc $_{z}$	max_acc $_{x}$	mean_acc $_{x}$	sd_gyr $_{y}$	sd_gyr $_{z}$
	(RF)	(sacrum)	(RF)	(sacrum)	(sacrum)	(RF)
Sacrum	min_acc $_{z}$	sd_acc $_{z}$	ent_gyr $_{z}$	sd_gyr $_{x}$	sd_gyr $_{y}$	ent_acc $_{z}$
Withers	sd_acc $_{z}$	p75_acc $_{x}$	sd_acc $_{x}$	mean_gyr $_{z}$	ent_acc $_{z}$	sd_gyr $_{z}$
Poll	fft $_{3}$ _acc $_{z}$	sd_acc $_{x}$	sd_gyr $_{y}$	ent_acc $_{z}$	krt_acc $_{z}$	ent_acc $_{x}$
RF	p25_gyr $_{z}$	max_acc $_{x}$	sd_gyr $_{z}$	mdn_gyr $_{z}$	sd_gyr $_{y}$	sd_gyr $_{x}$
LF	p75_gyr $_{z}$	max_acc $_{x}$	sd_gyr $_{z}$	sd_acc $_{y}$	sd_gyr $_{y}$	mdn_gyr $_{z}$
RH	min_gyr $_{z}$	p75_gyr $_{z}$	mdn_acc $_{x}$	min_acc $_{x}$	mean_gyr $_{x}$	p75_acc $_{x}$
LH	max_gyr $_{z}$	p25_gyr $_{z}$	p75_acc $_{x}$	mean_gyr $_{x}$	min_acc $_{x}$	p75_acc $_{y}$

RF: Right front limb, LF: Left front limb, RH: Right hindlimb, LH: Left hindlimb; gyr_x,y,z: x, y, and z axis of angular velocity signal.