Table 3.
Model-fitting Statistics for Bivariate ACE Model
| Overall Fit of Modela | Relative Fit of Modelb | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Variable and Model | -2LL | df | χ2 | df | p | AIC | Δχ2 | df | p |
| Home | |||||||||
| Actigraph - TBAQ | |||||||||
| Saturated | 6669.795 | 1208 | |||||||
| Full | 6676.629 | 1219 | 6.384 | 11 | .812 | -15.166 | |||
| Drop rg | 6680.494 | 1220 | 10.699 | 12 | .555 | -13.301 | 3.865 | 1 | .049 |
| Drop rc | 6678.523 | 1220 | 8.728 | 12 | .726 | -15.272 | 1.894 | 1 | .325 |
| Drop re | 6676.632 | 1220 | 6.837 | 12 | .867 | -17.163 | 0.002 | 1 | .964 |
| Drop rc & re | 6678.573 | 1221 | 8.778 | 13 | .789 | -17.221 | 1.944 | 2 | .378 |
| Lab | |||||||||
| Actigraph - IBR | |||||||||
| Saturated | 4777.183 | 1220 | |||||||
| Full | 4790.314 | 1231 | 13.131 | 11 | .285 | -8.869 | |||
| Drop rg | 4797.262 | 1232 | 20.079 | 12 | .070 | -3.921 | 6.948 | 1 | .008 |
| Drop rc | 4791.416 | 1232 | 14.233 | 12 | .289 | -9.767 | 1.102 | 1 | .294 |
| Drop re | 4835.375 | 1232 | 58.192 | 12 | .000 | 34.192 | 45.061 | 1 | .000 |
Note. -2LL=Likelihood Statistic. χ2=Chi-square fit statistic. df=Degrees of freedom. AIC=Akaike's Information Criterion. rg=genetic correlation, rc=shared environmental correlation, re=nonshared environmental correlation. Best fitting model indicated in bold.
a
Overall fit of the model is determined by the difference in -2LL of the model and that of a saturated model.
b
Relative fit of the model determined by the χ2 difference (Δχ2) between full bivariate ACE model and reduced model.