Some Exact Percentage Points of a Statistic Useful in Analysis of Variance and Principal Component Analysis

Some exact percentage points are given for the ratio of the largest eigenvalue to the trace of Z′Z, where Z is a matrix having independent standard normal variates as entries. These percentage points are useful in certain analysis of variance models for two-way cross-classilied data, for which only approximations have been given to date. They also have implications for principal component analysis.