Table 4. The effect of modality on the stress and subject identification performance (virtual environment for real-time biometric interaction and observation).

Modalities and task		Approach
		Centralized			FLa			FL+DPb
		ACCc	F 1	AUCd	ACC	F 1	AUC	ACC	F 1	AUC
ACC
	Stress	90.61	82.56	91.50	85.48	80.13	86.45	82.18	77.02	83.03
	Subject Identification	86.42	83.00	87.12	84.40	79.16	85.00	63.60	58.46	63.60
BVPe
	Stress	92.96	88.87	93.00	88.95	83.84	90.56	85.00	80.00	85.00
	Subject Identification	85.63	80.31	86.33	80.86	74.37	90.13	48.64	42.51	49.00
EDAf
	Stress	93.16	89.01	94.56	92.46	88.23	93.00	89.24	84.06	90.01
	Subject identification	88.30	83.12	88.30	83.83	78.65	84.23	45.12	38.01	46.00
TEMPg
	Stress	92.64	88.37	93.34	90.42	85.12	90.42	86.32	81.12	87.06
	Subject identification	85.34	80.07	86.17	82.56	76.33	82.56	39.59	31.42	40.00
All
	Stress	95.00	91.01	95.00	93.96	89.88	94.00	90.94	85.89	90.94
	Subject Identification	90.00	85.01	90.00	88.92	83.84	89.10	38.46	30.18	39.35

^aFL: federated learning.

^bDP: differential privacy.

^cACC: acceleration.

^dAUC: area under the curve.

^eBVP: blood volume pulse.

^fEDA: electrodermal activity.

^gTEMP: skin temperature.