The
sids data frame contains counts of sudden infant deaths for 1974 to
1978 along with related information in 100 counties in North Carolina.
DATA DESCRIPTION:
The data frame contains the following columns:
ARGUMENTS:
id
an identifying number for the county (in the range 1 to 100).
easting
the x coordinate of the county relative to an arbitrary origin, where
the x-axis is parallel to the latitude.
northing
the y coordinate of the county relative to an arbitrary origin, where
the y-axis is parallel to the longitude.
sid
the number of SIDS deaths in the county during the years 1974 to 1978.
births
the number of births in the county during years 1974 to 1978.
nwbirths
the number of nonwhite births, 1974 to 1978.
group
a grouping of the counties to one of 12 parcels of contiguous counties.
sid.ft
a dependent variable obtained as the Freeman-Tukey transformation of
the number of SIDS cases to the number of births during the years 1974
to 1978.
nwbirths.ft
an independent variable derived as the Freeman-Tukey square root
transformation of the ratio nonwhite births to the number of births
during the years 1974 to 1978.
SOURCE:
The data are listed and analyzed in Cressie and Chan (1989).
REFERENCES:
Cressie, Noel and Chan, Ngai H. (1989).
Spatial modeling of regional variables.
Journal of the American Statistical Association84, 393-401.