Approximation of Probabilities Near the Median of the F Distribution

Abstract

Jaspen has provided a fairly accurate and widely used method of approximating probabilities corresponding to values of the F ratio. However, the approximation is inaccurate when F is between unity and the median. A minor modification of the method provides more nearly accurate estimates of the probabilities for F values in this range than those afforded by Jaspen's procedure. Changes are suggested in Jaspen's computer program for calculating the probabilities.