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 |

`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 1.3-30 Index]