Improved Confidence Intervals for the Ratio of the Variances and Standard Deviations from Two Normal Populations.

摘要

Shortest confidence intervals for the ration of two variances of normal populations are found as superior alternatives to the widely used equal tail confidence intervals. Extensive tables of high precision are presented which enable the user to easily construct shortest confidence intervals for the ratio of two variances, the ratio of two standard deviations and the shortest unbiased confidence interval for the ratio of two variances. Characteristics and improved performance of the alternative confidence intervals are discussed in detail and illustrated graphically, with an emphasis on the optimal distribution of complementary tail area between the upper and lower tails. (Author)