Table 1.

Means and Standard Deviations of Measures Used in Analyses (N = 2,976)

	Mean	Std. Dev.	Minimum	Maximum
Focal Child’s HOME Score before younger sibling’s birth	976.30	161.38	80.00	1293.00
Focal Child’s HOME Score after younger sibling’s birth	967.59	170.56	264.00	1319.00
Focal Child’s Behavioral Problems Index before younger sibling’s birth	105.69	14.98	68	149
Intention Status of Younger Sibling’s Birth
Intended	.62		0	1
Unintended (either unwanted or mistimed)	.38		0	1
Unwanted	.14		0	1
Mistimed	.24		0	1
Intention Status of Focal Child’s Own Birth
Intended	.66		0	1
Unintended (either unwanted or mistimed)	.34		0	1
Unwanted	.07		0	1
Mistimed	.27		0	1
Family Characteristics (before younger sibling’s birth)
Family Income (in 1979 dollars)	$25,262	$51,907	0	$648,741
Home ownership	.48		0	1
Mother Living with spouse/partner	.71		0	1
Mother Living with Parents	.09		0	1
Number of mother’s children in household	2.20		0	9
Mother’s education	12.88		0	20
Mother’s Armed Forces Qualifying Test score  (AFQT)	39.19		1.00	99.00
Mother’s age at focal child’s birth	25.00	4.37	15	41
Race/ethnicity:
Non-Hispanic white	.50		0	1
Latina	.23		0	1
African-American	.27		0	1
Region of residence:
South	.31		0	1
Northeast	.17		0	1
North Central	.28		0	1
West	.24		0	1
Focal child female	.50		0	1
Focal child’s birth order	1.77		1	8
Characteristics of the focal child’s assessment
Age at assessment (in months)	76.72	35.55	21	175
Temporal order	3.11	1.26	2	8
Total # assessments for this child	6.01	1.21	2	8
Wave	4.50	2.00	2	10
Younger sibling same sex as focal child	.48		0	1

Notes: All descriptive statistics in this table refer to the sample used in Table 2, where the dependent variable is the home observation of the environment score, except the statistics for the behavioral problems index, which refer to the sample used in Tables 3 through 5.