var.linear {boot} | R Documentation

## Linear Variance Estimate

### Description

Estimates the variance of a statistic from its empirical influence values.

### Usage

    var.linear(L, strata=NULL)

### Arguments

`L` | Vector of the empirical influence values of a statistic. These will usually be calculated by a call to `empinf`.
`strata` | A numeric vector or factor specifying which observations (and hence empirical influence values) come from which strata.

### Value

The variance estimate calculated from `L`.

### References

Davison, A. C. and Hinkley, D. V. (1997) Bootstrap Methods and Their Application. Cambridge University Press.

### See Also

`empinf`, `linear.approx`, `k3.linear`

### Examples

    #  To estimate the variance of the ratio of means for the city data.
    ratio <- function(d,w)
         sum(d$x * w)/sum(d$u * w)
    var.linear(empinf(data=city,statistic=ratio))

[Package boot version 1.2-24 Index]