k3.linear                package:boot                R Documentation

Linear Skewness Estimate

Description:

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

Usage:

     k3.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 which components of 'L') come from which strata. 

Value:

     The skewness 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', 'var.linear'

Examples:

     #  To estimate the skewness of the ratio of means for the city data.
     data(city)
     ratio <- function(d,w)
          sum(d$x * w)/sum(d$u * w)
     k3.linear(empinf(data=city,statistic=ratio))

