| var.linear {boot} | R Documentation |
Estimates the variance of a statistic from its empirical influence values.
var.linear(L, strata=NULL)
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. |
The variance estimate calculated from L.
Davison, A. C. and Hinkley, D. V. (1997) Bootstrap Methods and Their Application. Cambridge University Press.
empinf, linear.approx, k3.linear
# 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))