Linear Variance Estimate
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.
|
Description
Estimates the variance of a statistic from its empirical influence values.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.
data(city)
ratio <- function(d,w)
sum(d$x * w)/sum(d$u * w)
var.linear(empinf(data=city,statistic=ratio))