vcd: struc_assoc – R documentation

Pricing

Become an expert in R — Interactive courses, Cheat Sheets, certificates and more!

Get Started for Free

Documentation

vcd

struc_assoc

Core-generating Function for Association Plots

Description

Core-generating function for strucplot returning a function producing association plots.

Usage

struc_assoc(compress = TRUE, xlim = NULL, ylim = NULL,
  yspace = unit(0.5, "lines"), xscale = 0.9, gp_axis = gpar(lty = 3))

Arguments

`compress`	logical; if `FALSE`, the space between the rows (columns) are chosen such that the total heights (widths) of the rows (column) are all equal. If `TRUE`, the space between the rows and columns is fixed and hence the plot is more “compressed”.
`xlim`	either a 2 x k matrix of doubles, k the number of total columns of the plot, or a recycled vector from which such a matrix will be constructed. The columns of `xlim` correspond to the columns of the association plot, the rows describe the column ranges (minimums in the first row, maximums in the second row). If `xlim` is `NULL`, the ranges are determined from the residuals according to `compress` (if `TRUE`: widest range from each column, if `FALSE`: from the whole association plot matrix).
`ylim`	either a 2 x k matrix of doubles, k the number of total rows of the plot, or a recycled vector from which such a matrix will be constructed. The columns of `ylim` correspond to the rows of the association plot, the rows describe the column ranges (minimums in the first row, maximums in the second row). If `ylim` is `NULL`, the ranges are determined from the residuals according to `compress` (if `TRUE`: widest range from each row, if `FALSE`: from the whole association plot matrix).
`xscale`	scale factor resizing the tile's width, thus adding additional space between the tiles.
`yspace`	object of class `"unit"` specifying additional space separating the rows.
`gp_axis`	object of class `"gpar"` specifying the visual aspects of the tiles' baseline.

Details

This function is usually called by strucplot (typically when called by assoc) and returns a function used by strucplot to produce association plots.

Value

A function with arguments:

`residuals`	table of residuals.
`observed`	not used by `struc_assoc`.
`expected`	table of expected frequencies.
`spacing`	object of class `"unit"` specifying the space between the tiles.
`gp`	list of `gpar` objects used for the drawing the tiles.
`split_vertical`	vector of logicals indicating, for each dimension of the table, the split direction.

Author(s)

David Meyer David.Meyer@R-project.org

References

Cohen, A. (1980), On the graphical display of the significant components in a two-way contingency table. Communications in Statistics—Theory and Methods, A9, 1025–1041.

Friendly, M. (1992), Graphical methods for categorical data. SAS User Group International Conference Proceedings, 17, 190–200. http://datavis.ca/papers/sugi/sugi17.pdf

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. doi: 10.18637/jss.v017.i03 and available as vignette("strucplot").

Examples

## UCB Admissions
data("UCBAdmissions")
ucb <- aperm(UCBAdmissions)

## association plot for conditional independence
strucplot(ucb, expected = ~ Dept * (Admit + Gender),
  core = struc_assoc(ylim = c(-4, 4)), labeling_args = list(abbreviate = c(Admit = 3)))

vcd

Visualizing Categorical Data

v1.4-10

GPL-2

Authors

David Meyer [aut, cre], Achim Zeileis [aut] (<https://orcid.org/0000-0003-0918-3766>), Kurt Hornik [aut], Florian Gerber [ctb], Michael Friendly [ctb]

Initial release