Table 2. Results of the Factor Analysis (FA) and transformations applied.

	Parameters	Transformation	Factors
			1	2	3	4	5	6
	call duration [s]	log(x)	−0.08	0.03	0.04	−0.05	0.89	0.03
Mean	element duration [s]		0.13	0.64	−0.26	0.25	0.24	−0.41
	interval duration [s]	sqrt(x-min(x))	0.06	0.43	−0.17	0.12	0.63	−0.47
	start F0 [Hz]		0.68	0.01	−0.07	0.04	−0.20	0.58
	end F0 [Hz]		0.88	−0.12	0.08	0.11	−0.17	0.17
	mean F0 [Hz]		0.95	0.05	0.06	0.03	−0.05	0.12
	max F0 [Hz]		0.93	0.11	−0.06	−0.02	0.07	0.09
	location of max F0 [s]	sqrt(x)	0.16	0.19	−0.20	0.77	0.03	−0.38
Maximum	element duration [s]		−0.07	0.89	−0.01	0.07	0.22	−0.04
	interval duration [s]	log(x)	−0.03	0.52	−0.02	0.01	0.78	−0.06
	start F0 [Hz]		0.44	−0.05	0.12	0.02	0.08	0.81
	end F0 [Hz]	sqrt(x-min(x))	0.71	−0.06	0.51	−0.01	−0.01	0.17
	mean F0 [Hz]	sqrt(x-min(x))	0.69	−0.01	0.54	0.06	0.01	0.13
	max F0 [Hz]		0.69	−0.09	0.40	−0.08	0.23	0.13
	location of max F0 [s]	sqrt(x)	−0.01	0.04	0.03	0.95	0.08	0.10
Variation	element duration [s]	sqrt(x)	−0.03	0.94	−0.01	0.07	−0.02	0.06
	interval duration [s]	log(x)	0.04	0.66	−0.02	0.06	0.55	0.13
	start F0 [Hz]	sqrt(x)	0.35	0.05	0.16	0.05	−0.03	0.82
	end F0 [Hz]	sqrt(x)	0.41	0.15	0.69	−0.11	−0.10	0.13
	mean F0 [Hz]	sqrt(x)	0.06	−0.02	0.88	0.07	−0.12	0.07
	max F0 [Hz]	sqrt(x)	0.05	−0.18	0.71	−0.07	0.13	0.05
	location of max F0 [s]	sqrt(x)	−0.03	0.10	0.04	0.94	−0.10	0.12
	Eigenvalues		6.62	4.45	2.48	1.84	1.50	1.23
	variance explained [%]		30.08	20.22	11.30	8.37	6.81	5.59

Indicated are the loadings of the acoustic parameters on the six derived factors (absolute loadings ≥0.5 are highlighted in boldface), Eigenvalues and percent variance explained by the factors. Mean  =  mean of calls' elements; Maximum  =  maximum value of calls' elements; Variation  =  variation of elements within a call.