Group Averages Over Level Combinations of Factors
Usage
ave(x, ..., FUN = mean)
Arguments
x
|
A numeric.
|
...
|
Grouping variables, typically factors, all of the same
length as x .
|
FUN
|
Function to apply for each factor level combination.
|
Description
Subsets of x[]
are averaged, where each subset consist of those
observations with the same factor levels.Value
A numeric vector, say y
of length length(x)
.
If ...
is g1,g2
, e.g.,
y[i]
is equal to FUN(x[j]
, for all j
with
g1[j]==g1[i]
and g2[j]==g2[i])
.See Also
mean
, median
.Examples
data(warpbreaks)
attach(warpbreaks)
ave(breaks, wool)
ave(breaks, tension)
ave(breaks, tension, FUN = function(x)mean(x, trim=.1))
plot(breaks, main =
"ave( Warpbreaks ) for wool x tension combinations")
lines(ave(breaks, wool, tension ), type='s', col = "blue")
lines(ave(breaks, wool, tension, FUN=median), type='s', col = "green")
legend(40,70, c("mean","median"), lty=1,col=c("blue","green"), bg="gray90")
detach()