nc.sids {spdep} | R Documentation

## North Carolina SIDS data

### Description

The `nc.sids` data frame has 100 rows and 9 columns. It contains data given in Cressie (1991, pp. 386-9), Cressie and Read (1985) and Cressie and Chan (1989) on sudden infant deaths in North Carolina for 1974-78 and 1979-84. The data set also contains the neighbour list given by Cressie and Chan (1989) omitting self-neighbours (ncCC89.nb), and the neighbour list given by Cressie and Read (1985) for contiguities (ncCR85.nb). The data are ordered by county ID number, not alphabetically as in the source tables `sidspolys` is a "polylist" object of polygon boundaries, and `sidscents` is a matrix of their centroids.

### Usage

    data(nc.sids)

### Format

This data frame contains the following columns:

CNTY.ID
  county ID
BIR74
  births, 1974-78
SID74
  SID deaths, 1974-78
NWBIR74
  non-white births, 1974-78
BIR79
  births, 1979-84
SID79
  SID deaths, 1979-84
NWBIR79
  non-white births, 1979-84
east
  eastings, county seat, miles, local projection
north
  northings, county seat, miles, local projection
x
  easting, county seats approximately reprojected to UTM zone 18
y
  northings, county seats approximately reprojected to UTM zone 18
lon
  easting, county seats in long-lat
lat
  northings, county seats in long-lat
L.id
  Cressie and Read (1985) L index
M.id
  Cressie and Read (1985) M index

### Source

Cressie, N (1991), Statistics for spatial data. New York: Wiley, pp. 386–389; Cressie, N, Chan NH (1989) Spatial modelling of regional variables. Journal of the American Statistical Association, 84, 393–401; Cressie, N, Read, TRC (1985) Do sudden infant deaths come in clusters? Statistics and Decisions Supplement Issue 2, 333–349; http://sal.agecon.uiuc.edu/datasets/sids.zip.

### Examples

    library(maptools)
    data(nc.sids)
    plot(sidspolys, border="grey", forcefill=FALSE)
    plot(ncCR85.nb, sidscents, add=TRUE, col="blue")
    plot(sidspolys, border="grey", forcefill=FALSE)
    plot(ncCC89.nb, cbind(nc.sids$lon, nc.sids$lat),
     add=TRUE, col="blue")

[Package spdep version 0.3-25 Index]