. Author manuscript; available in PMC: 2018 Jul 1.

Published in final edited form as: J Educ Psychol. 2017 Jul;109(5):680–693. doi: 10.1037/edu0000159

Table 2.

Variance Components Associated with Fixed Effects

	Model
	1	2	3	4	5
	Fixed Effect Spline Variance Component
IQ	-	-	0.0000	0.0000	0.0000
Reading (g-1)	-	-	0.0000	0.0000	0.0000
Central Executive	-	-	0.8860	0.3981	0.0919
Numerical Operations (g-1)	0.0000	-	-	-	-
Number Sets (g-1)	-	0.0000	-	0.0000	0.0000
Retrieval(g-1)	-	0.0000	-	0.0000	0.0000
Decomposition(g-1)	-	0.4709	-	0.8808	0.0000
Number line (g-1)	-	0.0000	-	0.0000	0.0000
Fractions comparison	-	-	-	-	0.0000
Random Effect Variance Component
Intercept	0.2581	0.3661	0.3309	0.2317	0.3144
Slope	0.0353	0.2325	0.5232	0.2569	0.0973
Spline	0.0000	6.6547	10.1853	6.6063	0.0000
Residual VC	0.3587	0.2405	0.2544	0.2341	0.1731
Mean R² over grade	.682	.822	.814	.828	.784