Burkitt's lymphoma in Uganda

Source: R/burk-data.R

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).

Source

The case data were extracted from the burkitt object of the splancs R package; see

Rowlingson B. and Diggle P.J. (2017), splancs: Spatial and Space-Time Point Pattern Analysis, R package version 2.01-40; https://CRAN.R-project.org/package=splancs.

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)
#> Marked planar point pattern:  188 points
#> Average intensity 0.01703669 points per square unit
#> 
#> *Pattern contains duplicated points*
#> 
#> Coordinates are integers
#> i.e. rounded to the nearest unit
#> 
#> marks are numeric, of type ‘double’
#> Summary:
#>    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
#>     413    2412    3704    3530    4700    5775 
#> 
#> Window: polygonal boundary
#> single connected closed polygon with 352 vertices
#> enclosing rectangle: [246.4, 341] x [237.6, 419.4] units
#>                      (94.6 x 181.8 units)
#> Window area = 11035 square units
#> Fraction of frame area: 0.642

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