A note on comparing several variances with a control variance

Consider the problem of comparing variances of k populations with the variance of a control population. When the experimenter has a prior expectation that the variances of k populations are not less than the variance of a control population, one-sided simultaneous confidence intervals provide more inferential sensitivity than two-sided simultaneous confidence intervals. But the two-sided simultaneous confidence intervals have advantages over the one-sided simultaneous confidence intervals as they provide both lower and upper bounds for the parameters of interest. In this article, a new multiple comparison procedure is developed for comparing several variances with a control variance, which provides two-sided simultaneous confidence intervals for the ratios of variances with the control variance and maintains the inferential sensitivity of one-sided simultaneous confidence intervals. Computation of the critical constants for the implementation of the proposed procedure is discussed and the selected critical constants are tabulated. (C) 2010 Elsevier B.V. All rights reserved.