1. If we are testing for the difference between the means of two (2) independent populations with samples n1 = 20 and n2 = 20, the number of degrees of freedom is equal to a. 39. b. 38. c. 19. d. 18. Q2. Given the following information, calculate the degrees of freedom that should be used in the pooled-variance t test: s12 = 4 and n1 = 16 s22 = 6 and n2 = 25 a. df = 41 b. df = 39 c. df = 16 d. df = 25 Q3. A supermarket is interested in finding out whether the mean weekly sales volume of Coca-Cola are the same when the soft drinks are displayed on the top shelf and when they are displayed on the bottom shelf. Ten stores are randomly selected from the supermarket chain with 5 stores using the top shelf display and 5 stores using the bottom shelf display. Assume that the samples are normally distributed with equal population variances. Refer to the sales volume data in the table below, what is the number of degree of freedom? Top Shelf Sales Volume 23 35 50 68 32 Bottom Shelf Sales Volume 55 70 72 51 63 a. 8 b. 3 c. 10 d. 12 Q4. A supermarket is interested in finding out whether the mean weekly sales volume of Coca-Cola are the same when the soft drinks are displayed on the top shelf and when they are displayed on the bottom shelf. Ten stores are randomly selected from the supermarket chain with 5 stores using the top shelf display and 5 stores using the bottom shelf display. Assume that the samples are normally distributed with equal population variances. Refer to the sales volume data in the table below, What are the critical values using a level of significance alpha=.01? Top Shelf Sales Volume 23 35 50 68 32 Bottom Shelf Sales Volume 55 70 72 51 63 a. +2.7638 and -2.7638 b. +2.8965 and -2.8965 c. +3.3554 and -3.3554 d. +4.5407 and -4.5407 Q5. A supermarket is interested in finding out wheather the mean weekly sales volume of Coca-Cola are the same when the softdrinks are displayed on the top shelf and when they are displayed on the bottom shelf. 10 stores are randomly selected from the supermaket chain with 5 stores using the top shelf display and 5 stores using the bottom shelf display. Assume that the samples are normally distributed with equal population variances. Refere to the sales volume data in the table below, Top shelf Sales Mean=41.6, Variance=249.84, Bottom shelf sales Mean=62.2, Variance=66.96. What is the sample pooled variance Sp2? Top Shelf Sales Volume 23 35 50 68 32 Bottom Shelf Sales Volume 55 70 72 51 63 a. 158.4 b. 11.995 c. 0 d. -11.995 Q6. A supermarket is interested in finding out whether the mean weekly sales volume of Coca-Cola are the same when the soft drinks are displayed on the top shelf and when they are displayed on the bottom shelf. 10 stores are randomly selected from the supermarket chain with 5 stores using the top shelf display and 5 stores using the bottom shelf display. Assume that the samples are normally distributed with equal population variances. Refer to the sales volume data in the table below, Top shelf Sales Mean=41.6, Variance=249.84, Bottom shelf sales Mean=62.2, Variance=66.96. What is the t-test statistic? Top Shelf Sales Volume 23 35 50 68 32 Bottom Shelf Sales Volume 55 70 72 51 63 a. -2.588 b. -9.405 c. 9.405 d. 2.13 Q7. When testing for the difference between the variances of two population with sample sizes of n1= 8 and n2= 10, the number of degrees of freedom is(are): a. 8 and 10. b. 7 and 9. c. 18. d. 16. Q8. If we are testing for the difference between the means of two (2) related populations with samples of n1 = 20 and n2 = 20, the number of degrees of freedom is equal to a. 39. b. 38. c. 19. d. 18. Q9. In testing for the differences between the means of two related populations, we assume that the differences follow a _______ distribution. a. normal b. odd c. sample d. population Q10. The objective of Analysis of Variance (ANOVA) is to analyze differences among the group means. a. true b. false Q11. The F test used for testing the difference in two population variances is always a one-tailed test. a. true b. false Q12. In testing for the differences between the means of two independent populations, we assume that the 2 populations each follow a _______ distribution. a. sample b. normal c. odd d. experiment Q13. The statistical distribution used for testing the difference between two population variances is the ___ distribution. a. t b. standardized normal c. binomial d. F Q14. One criterion used to evaluate employees in the assembly section of a large factory is the number of defective pieces per 1,000 parts produced. The quality control department wants to find out whether there is a relationship between years of experience and defect rate. A defect rate in terms of High, Average or Low is calculated for each worker in a yearly evaluation. The results for 100 workers based on years of experiences are given in the table below. Referring to the Table below, at alpha =0.05 level of significance, what would be the decision rule? <1 year <1-4 <5-9 high 9 average9 19 23 low 8 10 6 7 a. reject h0 if chi-square> 16.919 b. Reject H0 if chi-square > 15.507 c. Reject H0 if chi-square > 11.143 d. Reject H0 if chi-square > 9.488 Q15. If we use the chi-square method of analysis to test for the differences among 4 proportions, the degrees of freedom are equal to: a. 3 b. 4 c. 5 d. 1 Q16. The Marascuilo procedures allows one to make comparisons between all pairs of group to figure out which of the population proportions differ. a. true b. false Q17. A test for the difference between two proportions can be performed using the chi-square distribution. a. true b. false Q18. When testing for independence in a contingency table with 3 rows and 4 columns, there are________ degrees of freedom. a. 5 b. 6 c. 7 d. 12 Q19. One criterion used to evaluate employees in the assembly section of a large factory is the number of defective pieces per 1,000 parts produced. The quality control department wants to find out whether there is a relationship between years of experience and defect rate. A defect rate in terms of High, Average or Low is calculated for each worker in a yearly evaluation. The results for 100 workers based on years of experiences are given in the table below. Referring to the Table below, which test would be used to properly analyze the data in this experiment to determine whether there is a relationship between defect rate and years of experience? <1 above