Table 4.

Results of the SAB models of friendship network and marijuana (MJ) use dynamics in School 1

#	Model Parameter	MJ history (baseline)		MJ history +current MJ use		MJ history +risk factors
		Est.	SE	Est.	SE	Est.	SE
	Effects on Network Dynamics
1	Rate of change	8.86	0.46 **	8.88	0.53 **	8.81	0.48 **
2	Limited nominations on rate	−0.75	0.32 *	−0.74	0.38 +	−0.59	0.47
	Structural effects
3	outdegree (density)	−4.87	0.12 **	−4.95	0.12 **	−4.95	0.13 **
4	reciprocity	3.08	0.11 **	3.07	0.12 **	3.11	0.12 **
5	transitive triplets	0.71	0.07 **	0.71	0.06 **	0.70	0.08 **
6	3-cycles	−1.09	0.13 **	−1.08	0.12 **	−1.08	0.13 **
7	transitive ties	1.27	0.11 **	1.27	0.13 **	1.27	0.13 **
8	outdegree-popularity (sqrt.)	−0.48	0.08 **	−0.47	0.07 **	−0.52	0.08 **
	Control attributes
9	male alter	0.03	0.05	0.03	0.05	0.06	0.06
10	male ego	0.11	0.07 +	0.12	0.06 *	0.13	0.07 +
11	same male	0.32	0.05 **	0.32	0.05 **	0.32	0.06 **
12	same race	1.15	0.06 **	1.15	0.06 **	1.16	0.07 **
13	grade alter	0.19	0.05 **	0.19	0.05 **	0.19	0.06 **
14	grade ego	−0.14	0.07 *	−0.14	0.06 *	−0.13	0.06 *
15	same grade	0.41	0.05 **	0.41	0.05 **	0.40	0.05 **
16	parent education alter	0.08	0.03 **	0.08	0.02 **	0.06	0.03 *
17	parent education alter squared	0.01	0.02	0.01	0.03	0.01	0.03
18	parent education ego	−0.07	0.03 **	−0.07	0.03 *	−0.07	0.03 *
19	parent education similarity	0.21	0.11 +	0.21	0.12 +	0.21	0.12 +
20	limited nominations ego	0.23	0.16	0.23	0.18	0.20	0.15
	Risk and protective factors
21	neuroticism alter					0.00	0.01
22	neuroticism alter squared					0.00	0.00
23	neuroticism ego					−0.01	0.01
24	neuroticism similarity					0.17	0.23
25	delinquency alter					−0.03	0.03
26	delinquency alter squared					0.01	0.02
27	delinquency ego					0.03	0.04
28	delinquency similarity					0.41	0.15 **
29	GPA alter					0.13	0.04 **
30	GPA alter squared					−0.01	0.03
31	GPA ego					−0.05	0.04
32	GPA similarity					0.20	0.11 +
33	school attach alter					0.03	0.04
34	school attach alter squared					0.03	0.03
35	school attach ego					0.07	0.05
36	school attach similarity					0.19	0.16
37	school trouble alter					−0.06	0.04
38	school trouble alter squared					−0.02	0.03
39	school trouble ego					−0.18	0.05 **
40	school trouble similarity					0.11	0.17
	Any past month MJ use
41	current MJ use alter			0.06	0.09	0.11	0.09
42	current MJ use ego			−0.12	0.10	−0.08	0.10
43	same current MJ use			0.17	0.07 *	0.16	0.08 *
	Any history of MJ use
44	history of MJ use alter	−0.10	0.06 +	−0.10	0.08	0.01	0.07
45	history of MJ use ego	−0.16	0.07 *	−0.05	0.09	0.00	0.09
46	same history of MJ use	0.27	0.06 **	0.20	0.06 **	0.18	0.07 *
	Effects on History of MJ Use
47	Rate of change (i.e., initiation)	0.12	0.03 **	0.12	0.03 **	0.13	0.03 **
	Control attributes
48	male	0.49	0.29 +	0.48	0.28 +	0.30	0.30
49	outside-of-school friends	0.24	0.06 **	0.24	0.06 **	0.19	0.08 *
	Risk and protective factors
50	delinquency					0.25	0.16
51	GPA					−0.43	0.19 *
52	school trouble					0.36	0.19 +
	Friend influence
53	total friend exposure	0.52	0.16 **	0.52	0.17 **	0.50	0.18 **

Note. Model estimates (Est.) are unstandardized coefficients.

⁺p < .10,

^*p < .05,

^**p < .01