Table 1.

Descriptive Statistics for Study Variables

Variable and measurement age	n	M	SD	Minimum	Maximum	Skewness	Kurtosis
Academic achievement
4 years	908	0.00	0.68	−5.66	1.35	−1.09	6.03
15 years	668	0.00	0.74	−1.61	1.98	0.24	−0.36
Emotion regulation
4 years	646	0.00	0.78	−1.64	3.02	0.33	−0.29
15 years	875	0.00	0.90	−3.06	1.65	−0.58	−0.12
Personality
4 years	842	0.00	0.71	−2.89	2.27	0.01	0.47
15 years	866	0.00	0.86	−3.89	1.88	−0.47	0.28
Problem behavior
4 years	903	0.00	0.89	−2.08	3.02	0.33	−0.22
15 years	847	0.00	0.75	−1.28	4.24	1.15	2.12
Social skills
4 years	895	0.00	0.75	−2.95	1.98	−0.31	0.10
15 years	839	0.00	0.82	−3.20	1.52	−0.46	−0.16
Delay of gratification
4 years	840	4.55	2.98	0.00	7.00	−0.54	−1.55
Self-control
4–15 years	953	0.00	0.69	−2.35	1.94	−0.32	0.02
Social support
4–15 years	951	0.00	0.76	−3.06	1.87	−0.82	0.02

Note: All variables except delay of gratification are composites created from multiple measures. Measures were z scored with a mean of 0 and a standard deviation of 1 before being averaged to form composites. Descriptive information is reported for the continuous delay-of-gratification measure, which was dummy coded prior to analysis to address right censoring in the distribution.