Table 6.
Mixed models predicting academic skills from indicators of emotional-behavioral difficulties (Part 4).
| Mental Arithmetic Difficulties | ||||||
|---|---|---|---|---|---|---|
| Fixed Effects | b | SE | Df | T | LLCI | ULCI |
| Intercept | 0.064 | 0.096 | 16.810 | 0.667 | −0.139 | 0.268 |
| Sex | 0.378 *** | 0.090 | 390.936 | 4.179 *** | 0.200 | 0.557 |
| Conduct problems | 0.023 | 0.078 | 394.176 | 0.302 | −0.130 | 0.177 |
| Hyperactivity | 0.459 *** | 0.070 | 396.608 | 6.489 *** | 0.320 | 0.598 |
| Difficulties with peers | −0.034 | 0.070 | 399.414 | −0.494 | −0.173 | 0.103 |
| Emotional difficulties | 0.091 | 0.060 | 400.601 | 1.496 | −0.028 | 0.210 |
| Conduct problems X Sex | 0.368 * | 0.154 | 392.529 | 2.383 * | 0.064 | 0.673 |
| Hyperactivity X Sex | 0.179 | 0.137 | 388.996 | 1.306 | −0.090 | 0.449 |
| Difficulties with peers X Sex | −0.160 | 0.130 | 385.476 | −0.226 | −0.418 | 0.096 |
| Emotional difficulties X Sex | −0.053 | 0.114 | 389.004 | −0.471 | −0.278 | 0.170 |
| Random Effects | B | Z Wald | ||||
| Σu | 0.134 * | 2.215 * | ||||
| Σe | 0.721 *** | 13.811 *** | ||||
| Deviance | ||||||
| −2LL (df) | 1081.838 (12) | |||||
| AIC | 1085.838 | |||||
* p < 0.05. *** p < 0.001. Note: Sex: male −0.5 and female 0.5; such values allow interpreting the intercept value as referring to a generic child, with no sex assigned. LLCI, lower-level confidence interval (95%); ULCI, upper-level confidence interval (95%). σu: estimate of the residual error variance. σe: estimate of the intercept variance. −2LL: −2 Log likelihood. AIC: Akaike’s Information Criterion.