A stock analyst wants to determine whether there is a difference in the mean rate of return for three types of stock: utility, retail, and banking stocks. The following output is obtained: Analysis of Variance Source DF SS MS F P Factor 2 86.49 43.25 13.09 0.001 Error 13 42.95 3.30 Total 15 129.44 Level N Mean St. Dev ---------+------------+-------------+-------- Utility 5 17.400 1.916 (------*--------) Retail 5 11.620 0.356 (------*--------) Banking 6 15.400 2.356 (------*-------) Pooled st dev = 1.818 ---------+------------+-------------+-------- Find the 95% confidence interval for the difference between the mean rates of return for the utility and the retail stocks. (Round your answers to 2 decimal places.) 95% confidence interval is: ____ Solution A stock analyst wants to determine whether there is a difference in the mean rate of return for three types of stock: utility, retail, and banking stocks. The following output is obtained: Analysis of Variance Source DF SS MS F P Factor 2 86.49 43.25 13.09 0.001 Error 13 42.95 3.30 Total 15 129.44 Level N Mean St. Dev ---------+------------+-------------+-------- Utility 5 17.400 1.916 (------*--------) Retail 5 11.620 0.356 (------*--------) Banking 6 15.400 2.356 (------*-------) Pooled st dev = 1.818 ---------+------------+-------------+-------- Find the 95% confidence interval for the difference between the mean rates of return for the utility and the retail stocks. (Round your answers to 2 decimal places.) 95% confidence interval is: ____ ± ________ SOURCE DF SS MS F TREATMENT A 86.49 B C ERROR 13 42.93 3.30 D E STOCK TYPR N MEAN SD UTILITY 5 17.40 1.916 BANKING F 11.62 0.356 6 15.40 G A=2 B=43.25 C=13.09 D=15 E=129.44 F=5 F= 13.09 ,critical value is f(2,13)=3.81 =>reject null Means ALL MEANS ARE EQUAL MANY WAYS -DIFFEENCE IN MEANS TS=(5.78)/0.674= 8.578 UTILITY 15.6862775 17.40 19.1137 REALITY 11.30 11.62 11.93 SOURCE DF SS MS F TREATMENT A 86.49 B C ERROR 13 42.93 3.30 D E.

1. A stock analyst wants to determine whether there is a difference in the mean rate of return for
three types of stock: utility, retail, and banking stocks. The following output is obtained:
Analysis of Variance
Source DF SS MS F P
Factor 2 86.49 43.25 13.09 0.001
Error 13 42.95 3.30
Total 15 129.44
Level N Mean St. Dev ---------+------------+-------------+--------
Utility 5 17.400 1.916 (------*--------)
Retail 5 11.620 0.356 (------*--------)
Banking 6 15.400 2.356 (------*-------)
Pooled st dev = 1.818 ---------+------------+-------------+--------
Find the 95% confidence interval for the difference between the mean rates of return for the
utility and the retail stocks. (Round your answers to 2 decimal places.)
95% confidence interval is: ____
Solution
A stock analyst wants to determine whether there is a difference in the mean rate of return for
three types of stock: utility, retail, and banking stocks. The following output is obtained:
Analysis of Variance
Source DF SS MS F P
Factor 2 86.49 43.25 13.09 0.001
Error 13 42.95 3.30
Total 15 129.44
Level N Mean St. Dev ---------+------------+-------------+--------
Utility 5 17.400 1.916 (------*--------)
Retail 5 11.620 0.356 (------*--------)
Banking 6 15.400 2.356 (------*-------)
Pooled st dev = 1.818 ---------+------------+-------------+--------

2. Find the 95% confidence interval for the difference between the mean rates of return for the
utility and the retail stocks. (Round your answers to 2 decimal places.)
95% confidence interval is: ____ ± ________
SOURCE
DF SS
MS
F
TREATMENT
A
86.49
B
C
ERROR
13
42.93
3.30
D
E
STOCK TYPR
N
MEAN
SD
UTILITY
5
17.40
1.916
BANKING
F
11.62
0.356
6
15.40
G
A=2
B=43.25
C=13.09

3. D=15
E=129.44
F=5
F= 13.09 ,critical value is f(2,13)=3.81 =>reject null
Means ALL MEANS ARE EQUAL
MANY WAYS
-DIFFEENCE IN MEANS
TS=(5.78)/0.674= 8.578
UTILITY
15.6862775
17.40
19.1137
REALITY
11.30
11.62
11.93
SOURCE
DF SS
MS
F
TREATMENT
A
86.49
B
C
ERROR
13
42.93
3.30
D
E