Table 6.
Parameter estimates of the non-linear multivariate ACE model
| Parameter | Variable | Model | |
|---|---|---|---|
| Quadratic λ | Linear λ | ||
| λlin | MT | 1.00 | 1.00 |
| OA | 1.57 (0.12) | 1.56 (0.12) | |
| AR | 1.25 (0.11) | 1.25 (0.11) | |
| NS | 1.83 (0.14) | 1.82 (0.14) | |
| λquad | MT | 0.01 (0.07) | – |
| OA | 0.15 (0.05) | – | |
| AR | 0.06 (0.07) | – | |
| NS | 0.18 (0.05) | – | |
| σ2A | g | 0.40 (0.09) | 0.39 (0.09) |
| σ2C | g | 0.56 (0.12) | 0.56 (0.12) |
| σ2E | g | 0.05 (0.02) | 0.05 (0.02) |
| Model fit statistics | |||
|---|---|---|---|
| χ2(4) | – | 15.33 | |
| AIC | 14395.86 | 14402.42 | |
| BIC | 14508.38 | 14498.27 |
λlin is the baseline factor loading which models the linear relation between the phenotypic construct and the observed variables. λquad is the non-linearity parameter which accounts for the non-linearity in the relation between the phenotypic construct and the observed variable. χ2(4) is a Satorra–Bentler corrected likelihood ratio test between the model with non-linear and linear factor loadings
MT Mazes test, OA object aperture test, NS newcastle spatial test, AR simple arithmetic test