Table 2.
Twin and Bivariate Correlations
| Variables | Twin Correlations | Bivariate Correlations | ||||||
|---|---|---|---|---|---|---|---|---|
| MZF | DZF | MZM | DZM | DZO | 1 | 2 | 3 | |
| 1 Intoxication frequency | 0.50 | 0.28 | 0.63 | 0.30 | 0.20 | 1.00 | - | - |
| 2 Drinking frequency | 0.48 | 0.32 | 0.71 | 0.31 | 0.28 | 0.64*** | 1.00 | - |
| 3 Years of education | 0.72 | 0.49 | 0.76 | 0.51 | 0.41 | −0.11*** | .04* | 1.00 |
| N (twin pairs) | 344 | 297 | 265 | 271 | 618 | |||
MZF= monozygotic females; DZF= dizygotic females; MZM= monozygotic males; DZM= dizygotic males; DZO= dizygotic opposite sex
*
p<.05;
**
p<.01;
***
p<.001