Weighted Arithmetic Mean
Compute a weighted mean.
weighted.mean(x, w, ...)
## S3 method for class 'default': weighted.mean(x, w, \dots, na.rm = FALSE)
- an object containing the values whose weighted mean is to be computed.
- a numerical vector of weights the same length as
xgiving the weights to use for elements of
- arguments to be passed to or from methods.
- a logical value indicating whether
xshould be stripped before the computation proceeds.
This is a generic function and methods can be defined for the first
x: apart from the default methods there are methods
for the date-time classes
"Date". The default method will work for
any numeric-like object for which
[, multiplication, division
sum have suitable methods, including complex vectors.
w is missing then all elements of
x are given the
same weight, otherwise the weights coerced to numeric by
as.numeric and normalized to sum to one (if possible: if
their sum is zero or infinite the value is likely to be
Missing values in
w are not handled specially and so give a
missing value as the result. However, zero weights are handled
specially and the corresponding
x values are omitted from the
- For the default method, a length-one numeric vector.
## GPA from Siegel 1994 wt <- c(5, 5, 4, 1)/15 x <- c(3.7,3.3,3.5,2.8) xm <- weighted.mean(x, wt)