vcd (version 1.1-1)

spacings: Spacing-generating Functions

Description

These functions generate spacing functions to be used with strucplot to obtain customized spaces between the elements of a strucplot.

Usage

spacing_equal(sp = unit(0.3, "lines"))
spacing_dimequal(sp)
spacing_increase(start = unit(0.3, "lines"), rate = 1.5)
spacing_conditional(sp = unit(0.3, "lines"), start = unit(2, "lines"), rate = 1.8)
spacing_highlighting(start = unit(0.2, "lines"), rate = 1.5)

Arguments

start

object of class "unit" indicating the start value for increasing spacings.

rate

increase rate for spacings.

sp

object of class "unit" specifying a fixed spacing.

Value

• A spacing function with arguments:
• d
  "dim" attribute of a contingency table.
• condvars
  index vector of conditioning dimensions (currently only used by spacing_conditional).
• This function computes a list of objects of class "unit". Each list element contains the spacing information for the corresponding dimension of the table. The length of the "unit" objects is $k-1$, $k$ number of levels of the corresponding factor.

Details

These generating functions return a function used by strucplot to generate appropriate spaces between tiles of a strucplot, using the dimnames information of the visualized table.

spacing_equal allows to specify one fixed space for all dimensions.

spacing_dimequal allows to specify a fixed space for each dimension.

spacing_increase creates increasing spaces for all dimensions, based on a starting value and an increase rate.

spacing_conditional combines spacing_equal and spacing_increase to create fixed spaces for conditioned dimensions, and increasing spaces for conditioning dimensions.

spacing_highlighting is essentially spacing_conditional but with the space of the last dimension set to 0. With a corresponding color scheme, this gives the impression of the last class being highlighted in the penultimate class (as, e.g., in doubledecker plots).

References

Meyer, D., Zeileis, A., and Hornik, K. (2006), The strucplot framework: Visualizing multi-way contingency tables with vcd. Journal of Statistical Software, 17(3), 1-48. URL http://www.jstatsoft.org/v17/i03/ and available as vignette("strucplot").

See Also

strucplot, doubledecker

Examples

data("Titanic")
strucplot(Titanic, spacing = spacing_increase(start = 0.5, rate = 1.5))
strucplot(Titanic, spacing = spacing_equal(1))
strucplot(Titanic, spacing = spacing_dimequal(1:4 / 4))
strucplot(Titanic, spacing = spacing_highlighting,
                   gp = gpar(fill = c("light gray","dark gray")))
data("PreSex")
strucplot(aperm(PreSex, c(1,4,2,3)), spacing = spacing_conditional,
          condvars = 2)