In this note a generalization of a variance component test that was first suggested by Wald is examined. Necessary and sufficient conditions are given for the test to be applicable in a mixed linear model. A uniqueness property of the test in terms of degrees of freedom is also obtained.
"Applying Wald's Variance Component Test." Ann. Statist. 11 (1) 197 - 201, March, 1983. https://doi.org/10.1214/aos/1176346069