Table 1.

Results of linear regression analyses of variance in paternal caregiving

Actual caregiving	R2	Intercept	Variable	Standard β	t
Full model	0.35	83.7	Testosterone	−0.42	−3.07***
			Testes volume	−0.11	−0.83
			Father’s earnings	−0.13	−0.83
			Father’s hours worked	−0.24	−1.53
Reduced model	0.21	77.9	Testosterone	−0.34	−2.61**
			Testes volume	−0.23	−1.75*

Results of linear regression analyses showing the variance in paternal caregiving explained by the full model, which includes all variables correlated with caregiving in a simple correlation analysis, and the reduced model, which includes only measures of reproductive biology. *P < 0.10, **P < 0.05, and ***P < 0.005. P values are two-tailed.