Table 1.
Behavioral dimensions generated by factor analysis
| Factor | Eigenvalue | Behavior | Factor loading |
|---|---|---|---|
| 1. Gregariousness | 3.684 | Explore environment | 0.553 |
| Locomotion | 0.650 | ||
| Social contact-other | 0.411 | ||
| Mutual ventral | −0.914 | ||
| 2. Assertiveness | 1.714 | Explore environment | 0.520 |
| Vocalization | 0.845 | ||
| Aggression | 0.867 | ||
| 3. Attachment | 1.590 | Social contact-mother | 0.810 |
| Mutual break | 0.834 |
Behavioral dimensions generated by using factor analysis. Behaviors collected over the 18th through the 24th weeks of life were averaged, and extraction of Varimax rotated orthogonal factors identified three factors with eigenvalues >1.0 that together explained 58.0% of the variance. Based on the factor loadings, one of these was identified as infant attachment.