Table 1.
Means, standard deviations, ranges, and skewness for predictor variables before combination.
| Mean | SD | Maximum | Maximum | Skewness* | |
|---|---|---|---|---|---|
| Neighborhood measures: | |||||
| Rater report of risk | 6.97 | 1.55 | 4 | 13 | .81 |
| Mother report of problems | 9.83 | 2.74 | 6 | 24 | 1.27 |
| Mother report of social org. | 17.06 | 4.46 | 7 | 28 | −.03 |
| Temperament measures: | |||||
| Child report | |||||
| Fearfulness | 19.87 | 4.83 | 6 | 30 | −.23 |
| Irritability | 26.14 | 5.62 | 8 | 40 | −.12 |
| Impulsivity | 20.11 | 4.80 | 7 | 33 | .09 |
| Mother report | |||||
| Fearfulness | 17.59 | 3.94 | 8 | 29 | −.09 |
| Irritability | 26.81 | 5.43 | 11 | 40 | −.05 |
| Impulsivity | 22.35 | 4.33 | 11 | 33 | −.02 |
| Adjustment measures: | |||||
| Child report | |||||
| Depression/anxiety | 31.88 | 12.51 | 7 | 58 | −.22 |
| Conduct problems | 4.41 | 4.05 | 0 | 31 | 1.90 |
| Social competence | 61.96 | 9.16 | 20 | 80 | −.56 |
| Mother report | |||||
| Internalizing problems | 9.31 | 6.34 | 0 | 33 | .93 |
| Externalizing problems | 10.71 | 7.01 | 0 | 33 | .86 |
| Social competence | 42.22 | 7.04 | 18 | 56 | .14 |
*
All skew errors ranged from .136 to .138 (all rounded to .14). Several of the measures' skewness statistics were significant (>1.96). However, large samples give rise to small standard errors, and significant values arise from even small deviations from normality, thus, this criterion can be misleading. Skewness statistics were markedly reduced in the combined measures. Further, visual inspection of the histograms of the combined variables used in analyses suggested that all variables approximated normal distributions.