interaction2wt: Plot all main effects and twoway interactions in a multifactor design

Description

The main diagonal displays boxplots for the main effects of each factor. The off-diagonals show the interaction plots for each pair of factors. The i,j panel shows the same factors as the j,i but with the trace- and x-factor roles interchanged.

Usage

interaction2wt(x, ...)

## S3 method for class 'formula':
interaction2wt(x, data = sys.parent(), responselab, ...)

## S3 method for class 'default':
interaction2wt(x,
               response.var,
               responselab = deparse(substitute(y)),
               relation = list(x = "free", y = "same"),
               x.relation = relation$x,
               y.relation = relation$y,
               digits = 3,
               x.between = c(1, rep(0, ncol(x) - 1)),
               y.between = NULL,
               cex = 0.75,
               panel.input = panel.interaction2wt,
               strip.input = strip.interaction2wt,
               par.strip.text.input = list(cex = 0.7),
               scales.additional,
               main.in =
                 paste(responselab,
                       ": main effects and 2-way interactions",
                       sep = ""),
               xlab.in = TRUE,
               xlab = list(labels = ""),
               ylab = list(labels = ""),
               ...,
               main.cex)

Arguments

The object on which method dispatch is carried out. For the "formula" method, a formula describing the response variable and factors. The formula is generally of the form y ~ g1 + g2 + .... There may be one

data

For the formula method, a data frame containing values for any variables in the formula. In the R version, if not found in data, or if data is unspecified, the variables are looked for in the env

responselab

Character name of response variable, defaults to the name of the response variable in the formula.

...

additional arguments, primarily trellis arguments.

response.var

For the "default" method, the response variable. This is usually constructed by formula method from the input data and the input formula.

relation

trellis argument.

x.relation

x value of relation argument.

y.relation

y value of relation argument.

digits

doesn't do anything at the moment

x.between

x value of relation argument.

y.between

y value of relation argument.

cex

S-Plus: changes the size of the median dot in the boxplots. R: doesn't do anything.

panel.input

panel function. Default is panel.interaction2wt.

strip.input

strip function. Default is strip.interaction2wt.

par.strip.text.input

par.strip.text argument.

scales.additional

additional arguments to scales argument.

main.in

Text of main title.

xlab.in

S-Plus: FALSE suppresses x labels in trellis. R: no effect.

xlab

No effect.

ylab

No effect.

main.cex

cex for main title.

Value

"trellis" object containing the plot.

References

Heiberger, Richard M. and Holland, Burt (2004b). Statistical Analysis and Data Display: An Intermediate Course with Examples in S-Plus, R, and SAS. Springer Texts in Statistics. Springer. ISBN 0-387-40270-5.

Examples

Run this code

vulcan <- read.table(hh("datasets/vulcan.dat"), header=TRUE)
interaction2wt(wear ~ filler + pretreat + raw, data=vulcan)
if.R(r={
  ToothGrowth <- ToothGrowth  ## local copy
  ToothGrowth$dose <- ordered(ToothGrowth$dose) ## modify local copy
print(
  anova(aov(len ~ supp*dose, data=ToothGrowth))
)
print(
  interaction2wt(len ~ supp + dose, data=ToothGrowth)
)
print(
  bwplot(len ~ supp | dose, data=ToothGrowth, layout=c(3,1))
)
print(
  bwplot(len ~ dose | supp, data=ToothGrowth, layout=c(2,1),
         box.ratio=.5,
         panel=panel.bwplot.intermediate.hh,
         scales=list(x=list(at=position(ToothGrowth$dose))))
)
}, s={})