Two groups were polled about their attitudes towards capital punishment. In one group 30 out of 100 favored capital punishment, and in the other group 40 out of 80 favored capital punishment. Calculate an appropriate test value to test the hypothesis that the population proportions are the same.
A) -0.20
B) -2.73
C) -13.68
D) -37.40
1. In a multiple regression model y' = -10 + 2x1 + 19x2 + 14x3 + 2x4, if the x1 value changes by 2, then the predicted value for y will change by
A) 4
B) -6
C) 27
D) 38
2. The critical chi-square value for 15 degrees of freedom when and the test is right-tailed is 24.996.
A) True
B) False
3. A product testing laboratory selected a sample of 20 printers from 2 different manufacturers to determine if they could print more than 100,000 pages without breaking down. At , test the claim using Chi-Square that the proportions lasting more than 100,000 pages are equal.
Manufacturer 1 Manufacturer 2
Lasted past 100,000 12 8
Did not last to 100,000 8 12
Total 20 20
A) There is not evidence to reject the claim that the proportions are equal because the test value 1.600 < 3.841
B) There is evidence to reject the claim that the proportions are equal because the test value 3.841 > 1.600
C) There is not evidence to reject the claim that the proportions are equal because the test value 1.600 < 9.488
D) There is not evidence to reject the claim that the proportions are equal because the test value 9.488 > 1.600
4. In a multiple regression model y' = -10 + 2x1 + 19x2 + 14x3 + 2x4, if the x1 value changes by 2, then the predicted value for y will change by
A) 4
B) -6
C) 27
D) 38
5. The critical chi-square value for 15 degrees of freedom when and the test is right-tailed is 24.996.
A) True
B) False
6. When performing an F-test, if the means differ significantly, the between-group variance will be much larger than the within-group variance.
A) True
B) False
7. Which of the following assumptions is not made for the F test for comparing five or more means?
A) The populations from which the samples were obtained are approximately normally distributed.
B) The samples are independent of each other.
C) The sample sizes are equal.
D) The standard deviations of the populations are equal.
8. If the null hypothesis for the F-test has been rejected, a researcher can use either the Scheffé or Tukey test to determine where the difference in the means lies.
A) True
B) False
9. A researcher is performing a two-way ANOVA using two factors. The first factor has 4 levels and the second factor has 9 levels. In the ANOVA Summary Table, the degrees of freedom for the interaction between the first and second factors will be
A) 4
B) 13
C) 24
D) 36
10. Which of the following assumptions does not apply to the two-way ANOVA?
A) The populations from which the samples were obtained are at least approximately normally distributed.
B) The samples are independent of each other.
C) The standard deviations of the populations are approximately equal.
D) The sample sizes must be equal to or greater than 15.
11. A Two-Way ANOVA Summary Table is shown below.
Source SS d.f. MS F
Factor A 5.64 2 2.82 2.17
Factor B 9.98 2 4.99 3.84
Interaction A x B 7.38 4 1.85 1.42
Within (error) 35.10 27 1.3
Total 58.11 35
The critical value for the F test using = 0.05, d.f.N. = 2, and d.f.D = 27 is 3.35. Then,
A) the null hypothesis concerning Factor A should be rejected.
B) the null hypothesis concerning Factor B should be rejected.
C) the null hypothesis concerning Factor A and the Interaction (AxB) effect should be rejected.
D) all of the null hypotheses should be rejected.
12. If a researcher is using the paired-sample sign test and has 4 positive signs, 8 negative signs, and 3 zeros, what is the test value?
A) 3
B) 4
C) 8
D) 15
13. It was thought that hypnosis would lower a person's desire to smoke. A researcher decided to investigate this hypothesis using a paired-sample sign test in which the number of cigarettes/day smoked by subjects was recorded before and after hypnosis. Given that the critical value for ten paired-samples at α = 0.05 in a one-tailed test is 1, is there enough evidence to support the hypothesis?
Subject 1 2 3 4 5 6 7 8 9 10
Before Hypnosis (Cigarettes/day) 18 20 25 15 19 21 30 16 13 20
After Hypnosis (Cigarettes/day) 16 18 24 10 20 23 26 15 14 18
A) Since the critical value is less than the test value, there is not enough evidence to reject the null hypothesis. Consequently, the data do not support the hypothesis that hypnosis reduces smoking.
B) Since the critical value is greater than the test value, there is not enough evidence to reject the null hypothesis. Consequently, the data do not support the hypothesis that hypnosis reduces smoking.
C) Since the critical value is less than the test value, there is enough evidence to reject the null hypothesis. Consequently, the data support the hypothesis that hypnosis reduces smoking. .
D) Since the critical value is greater than the test value, there is enough evidence to reject the null hypothesis. Consequently, the data support the hypothesis that hypnosis reduces smoking.
14. A researcher needs to conduct a suitable nonparametric test to compare two dependent variables. Which of the following should be used?
A) t-test
B) Wilcoxon rank sum test
C) Wilcoxon signed-rank test
D) Kruskal-Wallis test