A simple general method for constructing confidence intervals for functions of variance components

Abstract

A simple general method is proposed for constructing confidence intervals for arbitrary functions of variance components in balanced normal-theory models. The concept of "surrogate variables" is introduced as part of the description of the method. "Equal tail" and "shortest-length" confidence intervals from this method can be computed easily using simulations. As an illustration, the two-way random-effects model is considered. It is shown that the proposed method produces intervals that are comparable in confidence coefficient and average length to those produced by the best existing methods.