Calculate standard error of the mean.
Calculate standard error of the mean.
se(x, na.rm = FALSE)
x |
A vector. |
na.rm |
Logical: whether or not to remove NA values (default set to FALSE - including NAs). |
Standard Error of the mean.
Other Utility functions:
findAbsMin(),
find_n_neighbors(),
firstLetterCap(),
getArrowPos(),
getDec(),
getRange(),
getRatioCoords(),
get_palette(),
group_sort(),
inch2coords(),
isColor(),
list2str(),
move_n_point(),
orderBoxplot(),
sortGroups()
# load example data:
data(chickwts)
str(chickwts)
# first calculate means per feeding type:
avg <- with(chickwts, tapply(weight, list(feed), mean))
par(cex=1.25)
b <- barplot(avg, beside=TRUE, names.arg=FALSE, ylim=c(0,450))
text(b, rep(0, length(b)), labels=names(avg), srt=90, adj=-.25)
# calculate mean collapsing over feeding types:
abline(h=mean(avg), lwd=1.5, col='red1')
# add SE reflecting variation between feeding types:
abline(h=mean(avg)+c(-1,1)*se(avg), lty=2, col='red1')
text(getCoords(.5), mean(avg)+se(avg),
labels=expression('mean' %+-% '1SE'), pos=3, col='red1')
# Note that SE makes more sense for experiments with
# different groups or participants.Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.