TABLE 1.

Overall Twin Correlations, Variances, and Covariances for Twin 1 and Twin 2 in Female Danish Twin Pairs in MADT Sample

	COG1	ED1	AFB1	COG2	ED2	AFB2
COG1 …	12.20	.39	.13*	.35	.28	.12*
ED1.....	2.00	2.23	.24**	.28	.61	.18**
AFB1 …	2.18	1.74	24.31	.12*	.18**	.28
COG2 …	4.23	1.47	2.01	12.20	.39	.13*
ED2.....	1.47	1.36	1.34	2.00	2.23	.24**
AFB2 …	2.01	1.34	6.79	2.18	1.74	24.31

Note.— Correlations are above the diagonal, variances on the diagonal, and covariances below. COG = cognitive ability; ED = education; AFB = age at first birth. Suffix nos. indicate twin 1 or twin 2.

^*COG-AFB correlation.

^**ED-AFB correlation.