A researcher believes a new diet should improve weight gain.To test his hypothesis a random sample of 10 people on the old diet and an independent random sample of 10 people on the new diet were selected.The selected people on the old diet gain an average of 5 pounds with a standard deviation of 2 pounds,while the average gain for selected people on the new diet was 8 pounds with a standard deviation of 1.5 pounds. Assuming that the values are normally distributed in each population,the researcher would like to use the t procedure with pooled standard deviation using the F test.Using $\alpha$ = 0.05,the observed F value is _______.
A) 1.78
B) 3.79
C) -3.79
D) 3.18
E) 1.33

Question

Quizplus · Accepted Answer

The observed F value is the ratio of the variances of the two samples. The variance of the old diet is 2^2 = 4, and the variance of the new diet is 1.5^2 = 2.25. Therefore, the observed F value is 4 / 2.25 = 1.78.

A Researcher Believes a New Diet Should Improve Weight Gain α\alphaα

A Researcher Believes a New Diet Should Improve Weight Gain $\alpha$