Hi. This is just a multiple choice assignment that i need the answers to.. I don't need to show work
1. In a hypothesis test, if we failed to reject the null hypothesis, and the alternative hypothesis Hₐ was indeed the true state of nature, which of the following is true? a. We might have committed a type I error. b. We might have committed a type II error. c. We have definitely committed a type I error. d. We have definitely committed a type II error. 2. Type II error is committed when a. we don’t reject a null hypothesis that is true. b. we reject a null hypothesis that is true. c. we don’t reject a null hypothesis that is false. d. we reject a null hypothesis that is false. 3. In a hypothesis test, is we rejected the null hypothesis, which of the following is true? a. We might have committed a type I error. b. We might have committed a type II error. c. We have definitely committed a type I error. d. We have definitely committed a type II error. 4. The power of a test is measured by its capability of a. rejecting a null hypothesis that is false. b. not rejecting a null hypothesis that is false. c. rejecting a null hypothesis that is true. d. not rejecting a null hypothesis that is true. 5. If the p-value is less than alpha in a two-tailed test, a. the null hypothesis should be rejected. b. the null hypothesis should not be rejected. c. a one-tailed test should be used. d. no conclusion should be reached. 6. The symbol for the power of a statistical test is a. α b. 1 - α c. β d. 1 – β 7. Which of the following is a characteristic of the F distribution? a. Normally distributed b. Negatively skewed c. Equal to the t-distribution d. Positively skewed 8. If ANOVA is conducted and the null hypothesis is rejected, what does this indicate? a. The variances are the same b. All population means are different. c. At least one pair of population means is different. d. Too many degrees of freedom. 9. A large department store examined a sample of the 18 credit card sales and recorded the amounts charged for each of three types of credit cards: MasterCard, Visa, and Discover. Six MasterCard sales, seven Visa, and five Discover sales were recorded. The store used an ANOVA to test if the mean sales for each credit card were equal. What are the degrees of freedom for the F-statistic? a. 2 in the numerator, 15 in the denominator b. 6 in the numerator, 15 in the denominator c. 18 in the numerator, 3 in the denominator d. 3 in the numerator, 18 in the denominator 10. Analysis of variance is used to a. Compare nominal data b. Compute t-test c. Compare population proportion d. Simultaneously compare several population means 11. A given study is investigating the effects of 3 different educational interventions, comparing with a control group. They have 3 participants per group. At the 0.05 level, what is the critical value of F used to test the null hypothesis that the interventions are the same? a. 1.96 b. 4.07 c. 2.33 d. 12.00 12. In ANOVA, what is a factor? a. A dependent variable b. An independent variable c. A marginal mean d. An effect total 13. Why use degrees of freedom instead of sample or group size in ANOVA? a. to estimate parameters b. to estimate all possible samples c. to estimate effect size d. to estimate distribution if research hypothesis is true 14. When comparing more than two treatment means, why should you use an analysis of variance instead of using several t-tests? a. Using several t-tests increases the risk of a type I error. b. Using several t-tests increases the risk of a type II error. c. The analysis of variance is more likely to detect a treatment effect. d. There is no advantage to using an analysis of variance instead of several t-tests. 15. With ANOVA, if you designed your study well to see a difference between groups, you would expect to see a. between-group variance to be larger than within-group variance b. between-group variance to be larger than c. within-group variance to be larger than between-individual variance d. within-group variance to be larger than between-group variance 16. Analysis of variance is a statistical method of comparing the _____ of several populations. a. Standard deviations b. Variances c. Means d. Proportions e. None of the above 17. Given the table below, what is the F statistic? 18. To determine whether the test statistic of ANOVA is statistically significant, it can be compared to a critical value. What two pieces of information are needed to determine the critical value? a. Between-group variance, within-group variance b. Sample size, number of groups c. Mean, sample standard deviation d. Expected frequency, obtained frequency (For items 19 -24) To examine the effects of pets in stressful situations, researchers recruited 15 people to participate in an experiment. Subjects were randomly assigned to each of three groups to perform a stressful task alone (control group), with a Holland Lop bunny present, or with a Goldendoodle puppy present. Each subject’s mean heart rate during the task was recorded. Test the appropriate hypotheses at the α = 0.05 level to decide if the mean heart rate differs between the groups. You may manually calculate or use SPSS. 19. What would be the null hypothesis? 20. What would be the alternate hypothesis? 21. What is the analysis used? 22. What is your critical value? 23. What is your test statistic? 24. What is your conclusion? Include your interpretation of result in terms of this study. 25. What is the function of a post hoc tests in one-way ANOVA? a. Determine if any statistically significant group differences have occurred. b. Determine any presence of interaction effect between conditions. c. Identify groups that have reliable differences between group means. d. Set the critical value for the F-test 26. All factorial designs a. Have at least two independent variables. b. Have the potential for producing at least three main effects. c. Have the potential for producing at least two interaction effects. d. Have at least one independent variable and one dependent variable. 27. How many separate F-ratios are used in a 3x2x3 factorial design? a. 3 b. 6 c. 7 d. 18 28. Factorial designs allow us to study both _____effects of the independent variables on the dependent variables. a. Dependent and independent b. Symbiotic and dichotomous c. Rank order and correlational d. Main and interactive 29. A 2x3 factorial design has 6 a. Independent variables b. Different conditions c. Levels of the independent variable d. Subjects per condition 30. A 2x4 factorial design has a. Eight different conditions b. An independent variable with four levels c. Two different independent variables d. All of the above 31. In a factorial study, what is a main effect? a. It refers to any statistically significant finding in the study. b. It refers to any statistically significant difference between the levels of a single independent variable. c. It occurs when the effect of one variable depends on the level of the other variable. d. It is the highest significance of an effect observed. 32. In a 2 (gender) x 2 (type of therapy) factorial design, males were helped by therapy A, but females were helped by therapy B. This describes a. A main effect for therapy type b. A main effect for gender c. An interaction between gender and therapy type d. None of the above 33. What does an A*B interaction mean in a factorial ANOVA? a. There must be significant main effects for factors A and B. b. The main effects for factors A and B must be short of significance. c. The effect of factor A depends on the level of factor B. d. a & c 34. Factorial designs a. Include no more than one research hypothesis b. Cannot test participants across more than one condition. c. Are ineffective when matched participants are included. d. Contain more than one null hypothesis. 35. What information is given in the 2 x 3 x 2 factorial design? a. Interactions will be found. b. The design has 12 independent variables. c. The design has three independent variables, two levels of A, three levels of B, and two levels of C. d. The design has two independent variables, three dependent variables, and two person variables. 36. Which of the following is correct? a. If there are no main effects, there can be no interactions. b. Whenever interactions are found, there must be main effects. c. Whenever main effects are found, there must be at least one interaction. d. When both interactions and main effects are found, the interactions are interpreted first. (For items 37 - 39) A teacher has recently learned that some people can be predictably categorized as an “early bird” versus a “late-nighter”. He wonders if the early birds actually score better than late-nighters on a standard 20-item test at 7:30am, and if the late-nighters perform better when they take a 1:30pm test. The teacher takes two classes of students, one which is to take a 7:30am final exam and one which is to take a 1:30pm final exam. Based on a personality test, he divides each class into early birds and late-nighters. He then finds the number of errors made on the 20-item test. The following is the data set: 37. Run your analysis on SPSS. Include your output here. 38. What analysis did you perform? 39. Interpret your result in terms of this study. 40. A sport school offers a special activity program for people who want to lose weight. The weights of 25 participants of the program and 25 people who did not participate were measured at the beginning of the program, after 4 weeks and after 3 months to evaluate the effect of the program over time. What statistical analysis would you use for this study? Why?