The California Child Health and Development Study involved women on the Kaiser
Health plan who received prenatal care and later gave birth in the Kaiser
clinics.  Approximately 19,000 live-born children were delivered in the 20,500
pregnancies. We consider the 680 live-born white male infants in the study.
Data were collected on a variety of features of the child, the mother, and the
father.

The columns in the data set are, from left to right:
 1) id      ID
 2) c_head  child's head circumference (inches)
 3) c_len   child's length (inches)
 4) c_bwt   child's birth weight (pounds)
 5) gest    gestation (weeks)
 6) m_age   maternal age (years)
 7) m_smok  maternal smoking (cigarettes/day)
 8) m_ht    maternal height (inches)
 9) m_ppwt  maternal pre-pregnancy weight (pounds)
10) p_age   paternal age (years)
11) p_educ  paternal years of education
12) p_smok  paternal smoking (cigarettes/day)
13) p_ht    paternal height (inches)