ciplot: Effect plot with multiple CIs for different groups

Description

Uses grayplot() to plot a set of confidence intervals.

Usage

ciplot(
  est,
  se = NULL,
  lo = NULL,
  hi = NULL,
  SEmult = 2,
  labels = NULL,
  rotate = FALSE,
  add = FALSE,
  offset = 0,
  ...
)

Value

None.

Arguments

est: Vector of estimates
se: Vector of standard errors
lo: Vector of lower values for the intervals
hi: Vector of upper values for the intervals
SEmult: SE multiplier to create intervals
labels: Labels for the groups (vector of character strings)
rotate: If TRUE, have group as y-axis; default (FALSE) has group on x-axis.
add: If TRUE, add the CIs to a previous plot with the same axes
offset: Amount to offset the positions of the confidence intervals (particularly for the case add=TRUE)
...: Optional graphics arguments

Details

Calls grayplot() with special choices of graphics parameters, as in dotplot().

Provide either se or both lo and hi. In the case that se is used, the intervals will be est +/- SEmult * se.

If labels is not provided, group names are taken from the names(est). If that is also missing, we use capital letters.

You can control the CI line widths with ci_lwd and the color of the CI segments with ci_col. You can control the width of the segments at the top and bottom with ci_endseg.

Examples

Run this code

set.seed(97536917)
x <- rnorm(40, c(1,3))
g <- rep(c("A", "B"), 20)
me <- tapply(x, g, mean)
se <- tapply(x, g, function(a) sd(a)/sqrt(sum(!is.na(a))))
ciplot(me, se) # default is +/- 2 SE
ciplot(me, se, SEmult=1)
ciplot(me, se, rotate=TRUE)
lo <- me - 2*se
hi <- me + 2*se
ciplot(me, lo=lo, hi=hi)

# show two sets of CIs side by side
colors <- crayons(c("Royal Purple", "Navy Blue"))
ciplot(me, se, SEmult=1, offset=-0.1,
       ci_col=colors[1], bg=colors[1],
       ylim=range(c(lo,hi)))
ciplot(me, lo=lo, hi=hi, add=TRUE, offset=0.1,
        ci_col=colors[2], bg=colors[2])