Panel function for confidence interval

Usage

panel.ci(
  x,
  y,
  lower,
  upper,
  groups = NULL,
  subscripts,
  col,
  fill = if (is.null(groups)) plot.line$col else superpose.line$col,
  alpha = 0.15,
  lty = 0,
  lwd = if (is.null(groups)) plot.line$lwd else superpose.line$lwd,
  grid = FALSE,
  ...,
  col.line = if (is.null(groups)) plot.line$col else superpose.line$col
)

Arguments

x, y

variables to be plotted in the scatterplot

lower

lower confidence limits

upper

upper confidence limits

groups

an optional grouping variable. If present, panel.superpose will be used instead to display each subgroup

subscripts

see lattice::xyplot()

col

line color

fill

fill color

alpha

opacity for the fill

lty

line type

lwd

line width

grid

A logical flag, character string, or list specifying whether and how a background grid should be drawn. This provides the same functionality as type="g", but is the preferred alternative as the effect type="g" is conceptually different from that of other type values (which are all data-dependent). Using the grid argument also allows more flexibility.

Most generally, grid can be a list of arguments to be supplied to panel.grid, which is called with those arguments. Three shortcuts are available:

TRUE:: roughly equivalent to list(h = -1, v = -1)
"h":: roughly equivalent to list(h = -1, v = 0)
"v":: roughly equivalent to list(h = 0, v = -1)

No grid is drawn if grid = FALSE.

...

Extra arguments, if any, for panel.xyplot. Usually passed on as graphical parameters to low level plotting functions, or to the panel functions performing smoothing, if applicable.

col.line

line color. Supersedes col if both are specified.

Examples

mod <- lm(Petal.Width ~ Petal.Length * Species, data = iris)
newdat <- expand.grid(
  Petal.Length = seq(1, 7, by = 0.1),
  Species = c("setosa", "versicolor", "virginica")
)
pred <- predict(mod, newdat, interval = "confidence")
dd <- cbind(newdat, pred)

xyplot(
  fit ~ Petal.Length,
  groups = Species, data = dd,
  prepanel = prepanel.ci, auto.key = list(lines = TRUE, points = FALSE),
  ylab = "Petal Width",
  xlab = "Petal Length",
  lower = dd$lwr, upper = dd$upr, type = "l",
  panel = function(...) {
    panel.ci(..., alpha = 0.15, grid = TRUE)
    panel.xyplot(...)
  }
)