SiZer (version 0.1-8)

ggplot_SiZer: Plot a SiZer map using `ggplot2`

Description

Plot a `SiZer` object that was created using `SiZer()`

Usage

ggplot_SiZer(x, colorlist = c("red", "purple", "blue", "grey"))

Arguments

x

An object created using `SiZer()`

colorlist

What colors should be used. This is a vector that corresponds to 'decreasing', 'possibley zero', 'increasing', and 'insufficient data'.

Author

Derek Sonderegger

Details

The white lines in the SiZer map give a graphical representation of the bandwidth. The horizontal distance between the lines is \(2h\).

References

Chaudhuri, P., and J. S. Marron. 1999. SiZer for exploration of structures in curves. Journal of the American Statistical Association 94:807-823.

Hannig, J., and J. S. Marron. 2006. Advanced distribution theory for SiZer. Journal of the American Statistical Association 101:484-499.

Sonderegger, D.L., Wang, H., Clements, W.H., and Noon, B.R. 2009. Using SiZer to detect thresholds in ecological data. Frontiers in Ecology and the Environment 7:190-195.

See Also

plot.SiZer, locally.weighted.polynomial

Examples

data('Arkansas')
x <- Arkansas$year
y <- Arkansas$sqrt.mayflies

plot(x,y)

# Calculate the SiZer map for the first derivative
SiZer.1 <- SiZer(x, y, h=c(.5,10), degree=1, derv=1, grid.length=21)
plot(SiZer.1)
plot(SiZer.1, ggplot2=TRUE)
ggplot_SiZer(SiZer.1)

# Calculate the SiZer map for the second derivative
SiZer.2 <- SiZer(x, y, h=c(.5,10), degree=2, derv=2, grid.length=21);
plot(SiZer.2)
plot(SiZer.2, ggplot2=TRUE)
ggplot_SiZer(SiZer.2)


# By setting the grid.length larger, we get a more detailed SiZer
# map but it takes longer to compute. 
#
# SiZer.3 <- SiZer(x, y, h=c(.5,10), grid.length=100, degree=1, derv=1)
# plot(SiZer.3)