Table 2.
Unconditional Growth Models for Low- and High-Complexity WPS
| Parameter | WPS performance
|
|
|---|---|---|
| Low complexity | High complexity | |
| Fixed effects | ||
| Average performance, Fall G3 (Intercept) | 24.5 | 8.4 |
| Initial linear growth, Fall G3 (Time) | 27.5 | 30.8 |
| Deceleration in growth from G3 through G5 (time squared) | −4.6 | −5.6 |
| Random effects | ||
| Intercept variance | 4.1 | 1.5 |
| Time variance | 0.5 | 0.7 |
| Intercept/time covariance | −0.1a | 0.2a |
| Error variance | ||
| Fall G3 | 1.7 | 1.3 |
| Spring G3 | 2.6 | 3.0 |
| Spring G4 | 2.2 | 3.8 |
| Spring G5 | 0.9 | 2.3 |
Note. The numbers reported are unstandardized coefficients, percent correct (out of 19 for low complexity and 20 points for high complexity) on the WPS tasks. WPS = word problem solving; G3–G5 = Grade 3–Grade 5.
a
Not significantly different from zero. All other effects are significant (p < .05).