Compute the design according to unequal weighting.

kishFactor(w)

Arguments

w

a numeric vector with weights

Value

The function will return the the kish factor

Details

The factor is computed acording to 'Weighting for Unequal P_i', Leslie Kish, Journal of Official Statistics, Vol. 8. No. 2, 1992 $$ deff = \sqrt n \sum_j w_j^2 / (\sum_j w_j)^2$$

Author

Alexander Kowarik

Examples

#> [1] 1
#> [1] 1.273886