Table 3. The effect of modality on the stress and subject identification performance (wearable stress and affect detection).

Modalities and task		Approach
		Centralized			FLa			FL+DPb
		ACCc	F 1	AUCd	ACC	F 1	AUC	ACC	F 1	AUC
ACC
	Stress	91.60	86.09	92.01	89.90	84.81	90.35	84.46	79.23	85.00
	Subject identification	95.50	91.70	96.00	94.88	90.76	96.34	58.19	52.01	60.00
BVPe
	Stress	98.34	96.14	99.13	96.05	92.01	97.00	90.97	86.92	92.46
	Subject identification	94.96	90.88	95.00	92.05	88.03	92.88	54.95	49.89	55.00
EDAf
	Stress	99.00	98.01	99.00	95.29	91.09	95.57	91.27	86.03	92.00
	Subject identification	86.15	70.06	86.88	85.89	80.78	86.27	50.05	43.00	50.05
ECGg
	Stress	97.01	95.00	97.02	93.37	89.03	94.00	91.60	86.45	92.10
	Subject identification	98.62	96.54	99.00	90.96	82.89	91.50	68.20	61.03	69.00
TEMPh
	Stress	99.00	98.00	99.00	94.88	90.76	95.23	90.00	85.00	90.00
	Subject identification	97.88	95.78	98.00	91.22	86.01	92.00	51.23	43.00	52.00
All
	Stress	99.86	96.72	99.86	95.56	91.38	96.13	90.00	85.00	90.00
	Subject identification	98.56	96.47	99.00	92.00	88.00	92.00	47.00	40.00	47.00

^aFL: federated learning.

^bDP: differential privacy.

^cACC: acceleration.

^dAUC: area under the curve.

^eBVP: blood volume pulse.

^fEDA: electrodermal activity.

^gECG: electrocardiogram.

^hTEMP: skin temperature.