Table 5.

Cross-Sectional and Within-MZ Twins Estimates, Non-Linear Specification of Schooling

	Cross-Sectional All Twins	Cross-Sectional Discordant Twins	Within-MZ Twins
	(1) OLS	(2) OLS	(3) OLS
Health Outcomes
BMI
12 grades	−0.950 (0.340)***	−.819 (.557)	−1.452 (0.546)***
14–16 grades	−1.228 (0.401)***	−1.22 (.550)**	−1.493 (0.549)***
17 grades	−2.339 (0.427)***	−1.39 (.624)	−1.805 (0.641)***
Overweight
12 grades	−0.040 (0.041)	0.027 (0.055)	−0.041 (0.058)
14–16 grades	−0.077 (0.042)	0.010 (0.058)	0.005 (0.068)
17 grades	−0.182 (0.045)	−0.025 (0.068)	−0.030 (0.083)
Short of Breath When Walking
12 grades	−0.082 (0.049)*	−0.016 (0.065)	−0.117 (0.078)
14–16 grades	−0.043 (0.050)	−0.053 (0.063)	−0.126 (0.082)
17 grades	−0.181 (0.050)***	−0.115 (0.071)*	−0.150 (0.092)*
Health-Related Behaviors
Never Smoked
12 grades	0.048 (0.041)	−0.028 (0.058)	−0.031 (0.061)
14–16 grades	0.114 (0.043)***	0.100 (0.059)*	−0.022 (0.071)
17 grades	0.179 (0.046)***	0.056 (0.069)	−0.003 (0.077)
Current Smoker
12 grades	−0.054 (0.028)*	−0.013 (0.044)	0.010 (0.056)
14–16 grades	−0.078 (0.028)***	−0.090 (0.04)**	−0.027 (0.061)
17 grades	−0.115 (0.028)***	−0.066 (0.048)	0.027 (0.065)
Alcohol Consumption
12 grades	0.484 (0.552)	1.07 (0.915)	0.545 (0.781)
14–16 grades	1.261 (0.696)	0.625 (1.15)	0.403 (1.122)
17 grades	1.089 (0.648)	0.725 (1.02)	0.491 (0.986)
Moderate or Heavy
Exercise during
Leisure Time
12 grades	0.058 (0.039)	0.005 (0.056)	−0.088 (0.077)
14–16 grades	0.056 (0.039)	0.022 (0.052)	−0.065 (0.083)
17 grades	0.102 (0.043)***	0.014 (0.065)	−0.090 (0.094)
N	1482	622	741

Notes: Columns 1 and 2 control for age and age squared. The reference schooling category is less than 12 grades. Standard errors in parentheses, clustered by twin pairs.

^***significant at 1%

^**significant at 5%;

^*significant at 10%.