Table 3. Confusion Matrix of the Time Spent Performing Activities Obtained from the Results of the Classification Model in UE Sessions.

		Class
		Walking	Sitting	Running	Lying down	Dynamic Standing	Overall
Real	Walking	7663	318	60	17	1471
	Sitting	515	80640	0	6495	2307
	Running	260	0	780	0	0
	Lying down	22	3855	0	69878	89
	Dynamic Standing	2418	1454	0	266	19937
Overall Accuracy (%) a							90±4
Sensitivity (%) b		78±16	89±11	64±27 f	95±4	80±7
F-Score (%) c		62±18	83±7	73±24 f	86±4	75±8
Specificity (%) d		90±2	88±4	100±0 f	87±6	90±2
Kappa e							0.85±0.00
Linear Weight Kappa							0.81±0.00
Quadratic Weighted Kappa							0.77±0.00
		Class
		Walking	Sitting	Running	Lying down	Dynamic Standing	Overall
Real	Walking	7663	318	60	17	1471
	Sitting	515	80640	0	6495	2307
	Running	260	0	780	0	0
	Lying down	22	3855	0	69878	89
	Dynamic Standing	2418	1454	0	266	19937
Overall Accuracy (%) a							90±4
Sensitivity (%) b		78±16	89±11	64±27 f	95±4	80±7
F-Score (%) c		62±18	83±7	73±24 f	86±4	75±8
Specificity (%) d		90±2	88±4	100±0 f	87±6	90±2
Kappa e							0.85±0.00
Linear Weight Kappa							0.81±0.00
Quadratic Weighted Kappa							0.77±0.00

^a Overall accuracy is the mean proportion of all activities that are correctly classified per person

^b Sensitivity corresponds to the chances of classifying an activity as positive when it is indeed positive

^c F-Score is defined as the "harmonic mean between sensitivity and positive predictive values" [18]

^d Specificity is a measure of chances of classifying an activity as negative when they are truly negative

^e Cohen’s Kappa is the measure of the agreement between the real activity and the classifications

^f Only three participants had practiced this activity.