Appendix C.

Factors Predicting Substance Dependency (Dichotomous specification, n=440)

	All					Male
	Marginal effect	Std. Err.	z	P>z		Marginal effect	Std. Err.	z	P>z
Female	−0.256	0.045	−5.130	0.000	***
Black	0.267	0.075	2.540	0.011	*	0.292	0.098	2.290	0.022	*
CPC preschool participation (ages 3-4)	0.003	0.055	0.050	0.963		−0.013	0.060	−0.220	0.829
Child protection services (ages 4-9)	0.047	0.070	0.670	0.502		0.059	0.105	0.560	0.573
Family conflict (ages 5-10)	0.263	0.083	3.090	0.002	**	0.249	0.108	2.190	0.028	*
CPC school age participation (ages 6-9)	−0.063	0.063	−1.010	0.312		−0.081	0.075	−1.080	0.279
Social maturity (ages 7-9)	−0.009	0.006	−1.540	0.124		−0.013	0.008	−1.550	0.120
Family risk (age 8)	−0.007	0.014	−0.490	0.621		−0.004	0.016	−0.270	0.790
Parent expectations (ages 8-10)	0.006	0.035	0.170	0.868		0.032	0.048	0.660	0.509
Intrinsic motivation (ages 9-10)	0.019	0.033	0.570	0.571		0.011	0.044	0.240	0.810
Reading achievement (age 10)	0.001	0.001	0.800	0.425		0.002	0.002	1.130	0.257
No trouble-making behavior (ages 9-12)	−0.036	0.016	−2.190	0.029	*	−0.038	0.020	−1.930	0.054
School quality (ages 10-14)	−0.164	0.094	−1.520	0.129		−0.152	0.117	−1.210	0.227
School mobility (ages 14-18)	0.050	0.047	1.070	0.282		0.055	0.054	1.020	0.310
Parent substance abuse experience (ages 10-15)	0.165	0.072	2.330	0.020	*	0.123	0.067	1.840	0.065
Deviant peer affiliation (age 16)	−0.016	0.049	−0.330	0.739		−0.012	0.066	−0.180	0.854
School dropout (by age 16)	0.008	0.065	0.120	0.903		0.002	0.064	0.020	0.980
Wald Chi-squared	319.97					250.06
Prob. > Chi-squared	0.00					0.00
Pseudo R-squared	0.12					0.08

Note:

^***p<0.001

^**p<0.01

^*p<0.05.

Probit coefficients are transformed to marginal effects (dy/dx), which are the change in substance dependency (in percentage points) per 1-unit change in the explanatory variables.