SiZer (version 0.1-8)

plot.SiZer: Plot a SiZer map Plot a SiZer object that was created using SiZer()

Description

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

Usage

# S3 method for SiZer
plot(
  x,
  ylab = expression(log[10](h)),
  colorlist = c("red", "purple", "blue", "grey"),
  ggplot2 = FALSE,
  ...
)

Arguments

x

An object created using SiZer()

ylab

What the y-axis should be labled.

colorlist

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

ggplot2

Should the graphing be done using `ggplot2`? Defaults to FALSE for backwards compatibility.

...

Any other parameters to be passed to the function image. Ignored if `ggplot2` is TRUE.

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)

# 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)

# 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)