. 2015 Dec 19;15(12):31999–32019. doi: 10.3390/s151229907

Table 10.

Results of body height and age classifications within participant subgroups using 10-fold cross-validation. The results show balanced correct classification rates, sensitivity, specificity, the positive predictive value (PPV) of each class and the average PPV of all classes.

Classification Task	Body Part	Sensor	Class. Rate	Sens.	Spec.	PPV $_{C_{1}}$	PPV $_{C_{2}}$	Avg. PPV
Body Height Classification
Male Group	Chest	A $_{x y z}$ , G $_{x y z}$	95.06	96.74	92.72	94.87	95.33	95.10
	Lower Back	A $_{x y z}$ , G $_{x y z}$	93.46	94.82	91.61	93.93	92.81	93.37
	Right Wrist	A $_{x y z}$ , G $_{x y z}$	93.50	96.77	89.07	92.31	95.32	93.81
	Left Ankle	A $_{x y z}$ , G $_{x y z}$	93.27	94.91	91.20	93.16	93.41	93.29
Female Group	Chest	A $_{x y z}$ , G $_{x y z}$	91.18	92.84	89.07	91.49	90.77	91.13
	Lower Back	A $_{x y z}$ , G $_{x y z}$	93.22	96.06	89.63	92.13	94.73	93.43
	Right Wrist	A $_{x y z}$ , G $_{x y z}$	89.34	92.97	84.90	88.30	90.78	89.54
	Left Ankle	A $_{x y z}$ , G $_{x y z}$	92.71	94.71	90.08	92.59	92.86	92.73
Age Classification
Male Group	Chest	A $_{x y z}$ , G $_{x y z}$	93.36	93.12	93.60	93.90	92.79	93.34
	Lower Back	A $_{x y z}$ , G $_{x y z}$	93.61	93.45	93.77	94.01	93.19	93.60
	Right Wrist	A $_{x y z}$ , G $_{x y z}$	93.55	94.40	92.65	93.19	93.95	93.57
	Left Ankle	A $_{x y z}$ , G $_{x y z}$	92.65	92.69	92.62	92.58	92.73	92.65
Female Group	Chest	A $_{x y z}$ , G $_{x y z}$	92.78	90.04	95.29	94.59	91.27	92.93
	Lower Back	A $_{x y z}$ , G $_{x y z}$	95.05	95.78	94.39	93.92	96.11	95.01
	Right Wrist	A $_{x y z}$ , G $_{x y z}$	87.97	88.79	87.20	86.62	89.29	87.96
	Left Ankle	A $_{x y z}$ , G $_{x y z}$	90.80	87.37	93.74	92.29	89.64	90.96