Mean
Weight
(lbs)502 CHAPTER 13 DESIGN AND ANALYSIS OF SINGLE-FACTOR EXPERIMENTS: THE ANALYSIS OF VARIANCEHousing Air Temperatures
(degrees F)
50 60 70 80 90 100
100 1.37 1.58 2.00 1.97 1.40 0.39
150 1.47 1.75 2.16 1.82 1.14 0.19
200 1.19 1.91 2.22 1.67 0.88 0.77(a) Does housing air temperature affect mean weight gain?
Use 0.05.
(b) Use Fisher’s LSD method to determine which tempera-
ture levels are different.
(c) Analyze the residuals from this experiment and comment
on model adequacy.
13-37. An article in Communications of the ACM(Vol. 30,
No. 5, 1987) studied different algorithms for estimating
software development costs. Six algorithms were applied to
eight software development projects and the percent error in
estimating the development cost was observed. The data are in
the table at the bottom of the page.(a) Do the algorithms differ in their mean cost estimation
accuracy? Use 0.05.
(b) Analyze the residuals from this experiment.
(c) Which algorithm would you recommend for use in
practice?
13-38. Consider an ANOVA situation with a4 means
1 1, 2 5, 3 8, and 4 4. Suppose that ^2 4,
n4, and 0.05.
(a) Find the power of the ANOVA F-test.
(b) How large would the sample size have to be if we want the
power of the F-test for detecting this difference in means
to be at least 0.90?
13-39. Consider an ANOVA situation with a5 treat-
ments. Let ^2 9 and 0.05, and suppose that n4.
(a) Find the power of the ANOVA F-test when 1 2
3 1, 4 3, and 5 2.
(b) What sample size is required if we want the power of the
F-test in this situation to be at least 0.90?Project
Algorithm 1 2 3 4 5 6 7 8
1(SLIM) 1244 21 82 2221 905 839 527 122
2(COCOMO-A) 281 129 396 1306 336 910 473 199
3(COCOMO-R) 220 84 458 543 300 794 488 142
4(COCOMO-C) 225 83 425 552 291 826 509 153
5(FUNCTION POINTS) 19 11 34 121 15 103 87 17
6(ESTIMALS) 20 35 53 170 104 199 142 41c 13 .qxd 5/8/02 9:21 PM Page 502 RK UL 6 RK UL 6:Desktop Folder:TEMP WORK:PQ220 MONT 8/5/2002:Ch 13: