Individual-level infant mortality data on 20000 randomly selected births of female babies in the U.S. state of North Carolina, in 2008, together with polygons describing the county shapes.
data(infants)
data(NC.polys)infants is a 20000 row data frame with the following columns:
Number code identifying North Carolina county in which birth occurred, and matching names(NC.polys). It can take 100 possible values.
Age of mother.
Completed weeks of gestation.
Equal to 1 if married, and 0 otherwise.
Infant's birth weight.
Equal to 1 if infant's birth weight < 2500 grams, and 0 otherwise.
Four categories of ethnicity: White, Hispanic, Black, Other.
Education of mother: Primary, Secondary, Tertiary.
Equal to 1 if smoker, and 0 otherwise.
Equal to 1 if it was the mother's first birth, and 0 otherwise.
Equal to 1 if completed weeks of gestation < 37.
NC.polys contains the polygons defining the areas in the format described below.
The data frame infants relates to the counties whose boundaries are coded in NC.polys.
NC.polys[[i]] is a 2 column matrix, containing the vertices of the polygons defining the boundary of the ith
county. names(NC.polys) matches infants$county (order unimportant).