Table 5.
Estimates from Biometric Growth Models with Covariates.
| Covariate Loading | Model Comp. | Intercept | Shape/Slope | Quadratic | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Covariate | N | Intercept | Shape/Slope | Quad. | Δ χ2 | Δ df | a 2 | c 2 | e 2 | a 2 | c 2 | e 2 | a 2 | c 2 | e 2 | |
|
TOWRE Sight
KG – 4th |
None | 972 | 0 | 0 | 0 | - | - | .82 | .11 | .08 | .79 | .07 | .14 | .84 | .03 | .13 |
| Parental Ed. | 972 | 27** | .10* | −15** | 15.99 | 18 | .87 | .05 | .08 | .76 | .09 | .14 | .84 | .03 | .13 | |
|
| ||||||||||||||||
| None | 784a | 0 | 0 | 0 | - | - | .84 | .07 | .09 | .79 | .06 | .15 | .85 | .01 | .14 | |
| School Lit. | 784a | 17** | .07 | −.09 | 23.37 | 18 | .85 | .06 | .09 | .78 | .07 | .15 | .84 | .02 | .14 | |
|
| ||||||||||||||||
|
TOWRE Decode
KG – 4th |
None | 972 | 0 | 0 | 0 | - | - | .87 | .02 | .11 | .78 | .09 | .13 | .80 | .04 | .16 |
| Parental Ed. | 972 | .26** | .20** | −.19** | 16.49 | 18 | .88 | .00 | .12 | .77 | .09 | .14 | .80 | .04 | .16 | |
|
| ||||||||||||||||
| None | 784a | 0 | 0 | 0 | - | - | .83 | .07 | .10 | .54 | .28 | .18 | .60 | .16 | .24 | |
| School Lit. | 784a | .18** | .13* | −.15* | 11.00 | 18 | .85 | .05 | .11 | .54 | .27 | .19 | .60 | .15 | .24 | |
|
| ||||||||||||||||
|
Passage Comp.
1st – 4th |
None | 972 | 0 | 0 | - | - | .72 | .16 | .12 | .27 | .36 | .37 | ||||
| Parental Ed. | 972 | 27** | .09 | 20.50 | 15 | .76 | .11 | .13 | .22 | .39 | .38 | |||||
|
| ||||||||||||||||
| None | 784a | 0 | 0 | - | - | .80 | .07 | .13 | .36 | .19 | .45 | |||||
| School Lit. | 784a | 19** | .12* | 20.51 | 15 | .84 | .03 | .13 | .32 | .21 | .47 | |||||
|
| ||||||||||||||||
|
WRAT Spelling
1st – 4th |
None | 972 | 0 | 0 | - | - | .74 | .11 | .15 | .32 | .35 | .32 | ||||
| Parental Ed. | 972 | 21** | 25** | 22.82 | 15 | .75 | .09 | .16 | .29 | .36 | .35 | |||||
|
| ||||||||||||||||
| None | 784a | 0 | 0 | - | - | .80 | .06 | .14 | .38 | .30 | .32 | |||||
| School Lit. | 784a | 13** | 17** | 12.16 | 15 | .81 | .05 | .14 | .38 | .29 | .34 | |||||
Note: Models analogous to the final models shown in Tables 2 and 3 and Figure 1, but were estimated in AMOS (Arbuckle, 2008) as Mx is unable to estimate loadings from the covariate onto the latent factors. Initial age in AMOS was controlled via covariate rather than definition variable. AMOS does not provide confidence intervals for the a2, c2, and e2 estimates. Covariate Load. = Standardized regression loading; Model Comp. = Nested χ2 model comparisons comparing model with covariate to model without covariate; a2 = proportion of variance due to genetic influences; c2 = proportion of variance due to shared environmental influences; e2 = proportion of variance due to non-shared environmental influences; Parental Ed. = Average of Maternal and Paternal Education; School Lit. = Average of School Reading and Writing Scores from the CSAP.
Only participants who attend public school have school literacy scores, leading to the lower N for those analyses.
p < .05,
p < .01