GeoBoxPlot {SpatialVx}

Geographic Box Plot

Description

Make a geographic box plot as detailed in Willmott et al. (2007).

Usage

GeoBoxPlot(x, areas, ...)

Arguments

x

numeric giving the values to be box-plotted.

areas

numeric of same length as x giving the associated areas for each value.

...

optional arguments to the boxplot function of R. The argument plot is not allowed.

Details

This function makes the geographic box plots described in Willmott et al. (2007) that calculates the five statistics in such a way as to account for the associated areas (e.g., over a grid where each grid box may have differing areas).

Missing values are not handled, and ideally should be handled before calling ths routine.

In future, this function may allow other options for x than currently, but for now, only numeric vectors are allowed.

Value

List with the same components as returned by boxplot.

Author(s)

Eric Gilleland

References

Willmott, C. J., Robeson, S. M. and Matsuura, K. (2007) Geographic box plots. Physical Geography, 28, 331–344, doi:10.2747/0272-3646.28.4.331.

See Also

boxplot

Examples

##
## Reproduce the boxplots of Fig. 1 in Willmott et al. (2007).
##
x <- c(4,9,1,3,10,6,7)
a <- c(rep(1,4),2,1,3)
boxplot( x, at=1, xlim=c(0,3))
GeoBoxPlot(x, a, at=2, add=TRUE)
axis( 1, at=c(1,2), labels=c("Traditional", "Geographic"))