A scientist is studying the relation between weight and horm

A scientist is studying the relation between weight and hormone levels. A random sample of rats is selected, and the sample is divided into two groups of five rats each. The rats in one group are given daily injections of a \'growth\' hormone, and the rats in the second group are injected with a harmless salt solution. During a 2-week test period, the psychologist records the amount of weight gained by each rat. The data are as follows: Are the variances equal Show your work.

Solution

The equality of variances are to be tested by F-test

F-stat = s₁² / s₂²

Where S₁ > S₂

Thus,

F-stat = 41 / 30 = 1.3666

F-crit _{0.05, 4,4} and F-crit_{0.95 ,4 ,4} are 6.38 and 0.156 respectively

Thus,

The null hypothesis can\'t be rejected. It means the two variances are equal.