R: Weighted mean and variance of a vector

wtd.mean {questionr} | R Documentation

## Weighted mean and variance of a vector

### Description

Compute the weighted mean or weighted variance of a vector.

### Usage

    wtd.mean(x, weights = NULL, normwt = "ignored", na.rm = TRUE)

### Arguments

`x` | Numeric data vector
`weights` | Numeric weights vector. Must be the same length as `x`
`normwt` | Only for `wtd.var`, if `TRUE` then weights are normalized for the weighted count to be the same as the non-weighted one
`na.rm` | if `TRUE`, delete `NA` values.

### Details

If `weights` is `NULL`, then an uniform weighting is applied.

### Author(s)

These functions are exact copies of the `wtd.mean` and `wtd.var` function from the wtd.stats package. They have been created by Frank Harrell, Department of Biostatistics, Vanderbilt University School of Medicine, <f.harrell@vanderbilt.edu>.

### See Also

`mean`,`var`, `wtd.table` and the `survey` package.

### Examples

    data(hdv2003)
    mean(hdv2003$age)
    wtd.mean(hdv2003$age, weights=hdv2003$poids)
    var(hdv2003$age)
    wtd.var(hdv2003$age, weights=hdv2003$poids)

[Package questionr version 0.6.3 Index]