Discussion:
Q1 An aircraft manufacturer is attempting to determine if the average leg length of the adult male has changed from 44". A sample of 81 men was selected randomly and the average length was found to be 45.5", with a standard deviation of 5.5". Test the null hypothesis that the average leg length of the adult male is 44", at & alpha = 0.05.
Q2 If Z = 1.96, standard deviation = 3, and B = 1, determine the correct sample size.
Q3 A marketing manager wants to determine if the advertising spending per month of his competitors is equal or not. Data over the last six months reveals the following figures (in thousands of dollars).
A B C
11 9 12
17 12 23
27 27 28
35 45 27
43 54 39
38 32 41
A.Calculate the SSE for these observations;
B.Compute the SST for these observations (answers below are rounded)
C.Calculate the F-ratio for the ANOVA based on these observations;
D.Find the F-value from the table in the back of the book to test the hypothesis that there is no difference in the average spending among these companies at alpha= 0.05
E.What is your null hypothesis? What is your alternative hypothesis? What your decision about the null hypothesis?