. Author manuscript; available in PMC: 2010 Sep 1.

Published in final edited form as: Intelligence. 2009 Sep 1;37(5):466–478. doi: 10.1016/j.intell.2009.05.006

Table 3.

Fit Statistics from the Models of Variance Components Allowing for Gene-Environment Interaction and Correlation

Model	-2*LL	df	χ²	Δdf	p	AIC
Grade Point Average at Age 17 as a Function of Age 11 IQ
All parameters free	6540.9	4196	---	---	---	6574.9
Fix common A, C, & E, unique A and C moderation paths to 0*	6545.4	4201	4.5	5	ns	6569.4
Fix all moderation paths to 0	6569.5	4202	24.1	1	<.001	6591.5
Educational Attainment at Age 24 as a Function of Age 17 IQ
All parameters free	5173.5	3340	---	---	---	5207.5
Fix common A and E, unique C and E moderation paths to 0*	5174.1	3344	.6	4	ns	5200.1
Fix all moderation paths to 0	5183.8	3346	9.7	2	.008	5205.8

Note: A refers to genetic influences, C to shared environmental influences, and E to nonshared environmental influences. There are possible common and unique moderation paths for each of A, C, and E. Best-fitting models are indicated by *. Fixed moderation paths were constrained to 0, which means that those sources of influence were present but did not vary across the levels of the moderators. AIC is Akaike Information Criterion.