Study Guide Data
Data Analysis and Decision
Help Session 5
Fall 2013
P1 Chi-square Test Goodness of Fit
A marketing company thinks that the proportion of people who prefer to get their news from different sources are the following: 25% from the TV, 43% from the Internet, 7% from the radio and 25% from the newspaper. In order to test their claim, they collect the following data:
Source
Internet
Radio
Newspaper
Count
TV
45
56
10
38
Can we be reasonably certain that their estimates are correct, at 5% significance level?
P2 Chi-square Test of Independence
A medical institute is interested in the relationship between a disease and exposure. A sample data is collected in the following contingency table.
Disease Yes
Total
Exposure Yes
37
13
50
Exposure No
17
53
70
Total
Disease No
54
66
120
At 5% significance level, does the data provide sufficient evidence to claim that the disease is associated with exposure? P3 ANOVA Test
Suppose an institute wants to examine the safety of compact cars, midsize cars, and full-size cars. It collects a sample of three for each of the treatments (cars types).
Test whether the mean pressure applied to the driver’s head during a crash test is equal for each types of car.
Use significance level at α= 5%.
Compact
Midsize
Full-Size
643
469
484
655
427
456
702
525
402
Mean
666.67
473.67
447.33
StDev
31.18
49.17
41.68
P4 ANOVA Test
An automobile manufacturer employs sales representatives who make calls on dealers. The manufacturer wishes to compare the effectiveness of four different call-frequency plans for the sales representatives. 32 representatives are chosen at random from the sales force and randomly assigned to the four call plans (eight per plan). The representatives follow their plans for six months, and their sales for the six-month study period are recorded. These
data
Help Session 5
Fall 2013
P1 Chi-square Test Goodness of Fit
A marketing company thinks that the proportion of people who prefer to get their news from different sources are the following: 25% from the TV, 43% from the Internet, 7% from the radio and 25% from the newspaper. In order to test their claim, they collect the following data:
Source
Internet
Radio
Newspaper
Count
TV
45
56
10
38
Can we be reasonably certain that their estimates are correct, at 5% significance level?
P2 Chi-square Test of Independence
A medical institute is interested in the relationship between a disease and exposure. A sample data is collected in the following contingency table.
Disease Yes
Total
Exposure Yes
37
13
50
Exposure No
17
53
70
Total
Disease No
54
66
120
At 5% significance level, does the data provide sufficient evidence to claim that the disease is associated with exposure? P3 ANOVA Test
Suppose an institute wants to examine the safety of compact cars, midsize cars, and full-size cars. It collects a sample of three for each of the treatments (cars types).
Test whether the mean pressure applied to the driver’s head during a crash test is equal for each types of car.
Use significance level at α= 5%.
Compact
Midsize
Full-Size
643
469
484
655
427
456
702
525
402
Mean
666.67
473.67
447.33
StDev
31.18
49.17
41.68
P4 ANOVA Test
An automobile manufacturer employs sales representatives who make calls on dealers. The manufacturer wishes to compare the effectiveness of four different call-frequency plans for the sales representatives. 32 representatives are chosen at random from the sales force and randomly assigned to the four call plans (eight per plan). The representatives follow their plans for six months, and their sales for the six-month study period are recorded. These
data