sparr (version 2.3-15)

burk: Burkitt's lymphoma in Uganda

Description

Data of the spatiotemporal locations of Burkitt's lymphoma in the Western Nile district of Uganda from 1960 to 1975.

Format

burk is a named list with three members:

$cases

An object of class ppp giving the spatial locations (eastings/northings) of the 188 cases of Burkitt's lymphoma recorded in individuals of various ages (mostly children); the spatial study region as a polygonal owin; as well as the time (in days since 1/1/1960) of each observation stored as the marks of the points.

$cases.age

A numeric vector of length 188 giving the age of each individual in $cases.

$controls

An object of class ppp giving 500 artificially simulated spatial-only observations to pose as a `control' data set representing the at-risk population. The data were generated from a smooth kernel estimate of the spatial margin of the cases. The similarity between the case point distribution and the true at-risk population dispersion can be seen in e.g. Figure 2 of Middleton and Greenland (1954).

References

Bailey, T.C. and Gatrell, A.C. (1995), Interactive spatial data analysis, Longman; Harlow.

Middleton, J.F.M. and Greenland, D.J. (1954), Land and population in West Nile District, Uganda, The Geographical Journal, 120, 446--455.

Examples

data(burk)
summary(burk$cases)

oldpar <- par(mfrow=c(1,3))
plot(burk$cases)
plot(burk$controls)
plot(density(marks(burk$cases)),xlim=range(marks(burk$cases)))
par(oldpar)