Table 3.
Differential Effects of Birth Weight
| Dependent Variable: High School IQ
| ||||
|---|---|---|---|---|
| Sample |
BDNF + COMT + APOE ≤ Median
|
BDNF + COMT + APOE > Median
|
||
| (1) | (2) | (3) | (4) | |
| Standardized Birth Weight | 2.5428*** (0.6528) | 1.8957* (1.1012) | 0.0192 (0.6694) | −0.6509 (0.8825) |
| Controls | ||||
| Demographic and Family SES | Y | Y | Y | Y |
| Sibling Fixed Effects | N | Y | N | Y |
| Test | ||||
| p-value for coeff. of col. (1) = coeff. of col. (3) | – | – | 0.0002 | – |
| p-value for coeff. of col. (2) = coeff. of col. (4) | – | – | – | 0.0042 |
|
| ||||
| N | 505 | 505 | 433 | 433 |
| R Sqr. | 0.1262 | 0.7671 | 0.1625 | 0.8312 |
Notes: (i) Columns (1) and (2) restrict the sample to individuals that have less than or equal to the median number of plastic alleles. Columns (3) and (4) restrict the sample to individuals to individuals with a greater than median number neuroplasticity alleles. (ii) The estimation of Table 3 is represented graphically by Figure 1. (iii) The distribution of additive genetic neuroplasticity score is given in Figure 2. (iv) Demographic and family controls include race, sex, birth year (age), birth order, mother’s education, father’s education, and a score for family SES in 1957. (iv) Standard errors are clustered at the family level with *, **, and *** representing significance at the 10, 5, and 1% significance level, respectively.