Chapter 9.4, Problem 19BB

Finding Lower Critical F Values For hypothesis tests that are two-tailed, the methods of Part 1 require that we need to find only the upper critical value. Let’s denote the upper critical value by F_R, where the subscript indicates the critical value for the right tail. The lower critical value F_L (for the left tail) can be found as follows: (l) Interchange the degrees of freedom used for finding F_R, then (2) using the degrees of freedom found in Step 1, find the F value from Table A-5; (3) take the reciprocal of the F value found in Step 2, and the result is F₁. Find the critical values F_L and F_R for Exercise 16 “Blanking Out on Tests.”