Table 4.

Direct and Indirect Effects of Working Memory-Numbers, Phonological Processing, and Processing Speed on Pre-Algebraic Knowledge (n=279)

Type of Effect	Effect of
	Working Memory-Numbers				Phonological Processing				Processing Speed
	path	S.E.	b/S.E.	p	path	S.E.	b/S.E.	p	path	S.E.	b/S.E.	p
Direct
Total Indirect	.052	.029	1.76	.078	.099	.029	3.37	.001	.089	.028	3.22	.001
via G2C	.000	.000	0.05	.961	.001	.007	0.11	.913	.002	.015	0.11	.914
G2W	.001	.007	0.20	.839	.002	.008	0.29	.770	.006	.007	0.83	.408
G3C	.042	.021	1.99	.047	.048	.019	2.58	.010	.026	.019	1.37	.171
G3W	.004	.008	0.50	.615	.016	.011	1.40	.161	.002	.008	0.30	.762

G=grade; C=calculations; W=word problems. Nonverbal reasoning is WASI-Matrix Reasoning. Language is a composite score across Wechsler Abbreviated Scale of Intelligence (WASI)-Vocabulary subtest and Woodcock Diagnostic Reading Battery-Listening Comprehension. Attentive Behavior is SWAN. Working Memory (WM)-Sentences and WM-Numbers, respectively, are Listening Recall and Counting Recall from the Working Memory Test Battery–Children. Phonological Processing is Comprehensive Test of Phonological Processing-Sound Matching. Processing Speed is Woodcock Johnson III Visual Matching. Grade 2 Calculations is Single-Digit Addition. Grade 2 Word Problems is Story Problems. Grade 3 Calculations is a composite score across Single-Digit Addition Double-Digit Addition and Double-Digit Subtraction Tests. Word Problems is the Iowa Test of Basic Skills- Problem Solving and Data Interpretation. Pre-algebraic knowledge is the Pre-Algebraic Knowledge Test.