. Author manuscript; available in PMC: 2013 Jan 14.

Published in final edited form as: J Educ Psychol. 2012;104(4):1083–1093. doi: 10.1037/a0029020

Table 3.

Cognitive Effects on Growth for Low- and High-Complexity WPS

Effect	Low complexity	High complexity
Intercept^a	24.6^*	8.4^*
Computation	2.2^*	0.6
Language	0.6^*	0.5^*
Nonverbal Reasoning	0.3^*	0.1
Attentive Behavior	0.1	0.2^*
Linear growth intercept^a	27.3^*	30.7^*
Computation	−0.8	0.9
Language	0.2	0.0
Nonverbal Reasoning	0.4^*	0.6^*
Attentive Behavior	0.6^*	0.3
Quadratic growth intercept^a	−4.6^*	−5.6^*
Computation	0.2	−0.4
Language	−0.1	0.1
Nonverbal Reasoning	−0.1	−0.2^*
Attentive Behavior	−0.2^*	0.0

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. Each effect represents the percentage of change in performance or growth rate for a unit change in the achievement or cognitive measure. For example, for low-complexity problems, a difference of one problem correct/minute in computational skill causes a 2.2% difference in initial WPS scores, a difference of 10 T-score points (1 SD) in nonverbal reasoning causes a difference of 4% (10 × 0.4) per year initial growth rate in WPS scores, and a difference of 12 points (1 SD) in attentive behavior causes a difference of 4.8% (12 × 0.2 × 2) per year in deceleration (i.e., yearly decrease in growth rate). WPS = word problem solving.

The Intercept is average performance beginning third grade at sample mean levels of computation, language, nonverbal reasoning, and attentive behavior. Linear and quadratic growth intercepts are the average growth rates beginning third grade at sample mean levels of the achievement and cognitive measures.

p < .05.