bplot {asbio} | R Documentation |
Creates barplots displaying treatment means with standard error or confidence interval error bars. Can also display letters indicating if results were significant after adjustment for simultaneous inference.
bplot(y, x, int = c("SE", "CI"), conf = 0.95, plot.ci = TRUE, bar = TRUE, simlett = FALSE, bar.col = "gray", lett = NULL, exp.fact = 2, xlab = "x", ylab = "y", err = "y", sfrac = 0.01, gap = 0, slty = par("lty"), scol = NULL, pt.bg = par("bg"), ...)
y |
A quantitative vector representing the response variable. |
x |
A categorical vector representing treatments (e.g. factor levels). |
int |
Type of error bar to be drawn, either "SE" of "CI" . |
conf |
Level of confidence, 1 - P(type I error). |
plot.ci |
Logical; indicating whether or not error bars are to be plotted. |
bar |
Logical; specifies whether a barplot or just error bars should be shown. |
bar.col |
Color of bar. |
simlett |
A logical statement indicating whether or not letters should be shown above bars indicating that populations means have been determined to be significantly different. |
lett |
A vector of letters or some other code to display multiple comparison results. |
exp.fact |
A multiplication factor indicating how much extra room is made for drawing letters in top of graph. Only used if simlett = TRUE . |
xlab |
X axis label for plot. |
ylab |
Y axis label for plot. |
err |
The direction of error bars: x for horizontal, y for vertical. |
sfrac |
Scaling factor for the size of the "serifs" (end bars) on the confidence bars, in x-axis units. |
gap |
Size of gap in error bars around points (default 0; for gap=TRUE gives gap size of 0.01). |
slty |
Line type for error bars. |
scol |
Line color for error bars. |
pt.bg |
Background color of points. If pch=NA , no points are drawn (e.g. leaving room for text labels instead). |
... |
Additional arguments from barplot . |
It is often desirable to display the results of a pairwise comparison procedure using sample means and error bars. This functions allows these sorts of plots to be made. Note that this function is essentially a wrapper for the function barplot
and plotCI
. Much of the documentation here follows directly from B. Boklker.
A plot is returned.
Ken Aho created the wrapper for barplot
. To create the function plotCI
Ben Bolker documented and tweaked a function provided by Bill Venables.
eggs<-c(11,17,16,14,15,12,10,15,19,11,23,20,18,17,27,33,22,26,28) trt<-c(1,1,1,1,1,2,2,2,2,2,3,3,3,3,4,4,4,4,4) bplot(y=eggs, x=trt,int="SE",xlab="Treatment",ylab="Mean number of eggs",names.arg=c(1,2,3,4),simlett=TRUE,lett=c("b","b","b","a"))