Stat 95

3. Identify the formula for the Pearson correlation coefficient.

A)

63. A researcher performs a 2 3 ANOVA with 5 participants in each cell of the study design. What is the within-groups degrees of freedom? A) 24 B) 6 C) 30 D) 22

A) 24

25. In which of the following situations would it be necessary to use a within-groups ANOVA? A) A longitudinal study follows a group of kindergarten children through high school and assesses their Body Mass Index at four timepoints. B) A researcher classifies a group of college students on the basis of their political leanings, as either liberal, conservative, libertarian, or green. C) A researcher is interested in the effects of distraction on driving performance and randomly assigns participants to one of three distraction groups. D) A researcher is interested in whether a sensitivity training class changes attitudes toward minority populations. The researcher assesses these attitudes before and after the sensitivity training class.

A) A longitudinal study follows a group of kindergarten children through high school and assesses their Body Mass Index at four timepoints

51. The figure reflects a main effect of study condition. What best describes that main effect? A) On average, people in the study-test condition had better memory than people in the study-study condition. B) Those in the study-test condition performed more poorly on the 5-minute recall test than did those in the study-study condition, but at longer retention intervals (2-day and 1-week), those in the study-test condition performed better than those in the study-study condition. C) On average, memory performance decreased as the retention interval increased. D) On average, people in the study-study condition had better memory than people in the study-test condition.

A) On average, people in the study-test condition had better memory than people in the study-study condition.

49. The probability of committing a ________ error greatly increases when we run multiple ________ tests to compare more than two groups. A) Type I; t B) Type II; t C) Type I; z D) Type II; F

A) Type I; t

67. The owners of the SciFi channel are interested in whether watching the SciFi channel causes people to become "geeky," and whether any such effects depend on a person's gender. They hire you to design and carry out the appropriate study. You design a study in which you ask an equal number of men and women to watch 0, 3, 5, and 9 hours of the SciFi channel each week for 6 weeks. At the end of each week, you measure the "geekiness" of the men and women on a scale from 1 to 10. How would you label the ANOVA used to analyze your data? A) a 2 4 mixed-design ANOVA B) a 2 4 between-groups ANOVA C) a 4 2 within-groups ANOVA D) a 2 2 mixed-design ANOVA

A) a 2 4 mixed-design ANOVA

47. The owners of the SciFi channel are interested in whether watching the SciFi channel causes people to become "geeky," and if so, whether any such effects depend on a person's gender. They hire you to design and carry out the appropriate study. You design a study in which you randomly assign an equal number of men and women to watch either 0, 3, 5, or 9 hours of the SciFi channel each week for 6 weeks. How would you label the ANOVA used to analyze your data? A) a 4 2 between-groups ANOVA B) a 4 2 within-groups ANOVA C) a 2 2 between-groups ANOVA D) a 2 2 within-groups ANOVA

A) a 4 2 between-groups ANOVA

54. Based on the figure, what effects appear to be present? A) a main effect of coping style and an interaction between coping style and cognitive strategy B) an interaction between coping style and cognitive strategy C) a main effect of coping style and a main effect of cognitive strategy D) a main effect of coping style, a main effect of cognitive strategy, and an interaction between coping style and cognitive strategy

A) a main effect of coping style and an interaction between coping style and cognitive strategy

50. Based on the cells of this study, what effects appear to be present? A) a main effect of study condition and an interaction between study condition and retention interval B) an interaction between study condition and retention interval C) a main effect of study condition, and a main effect of retention interval D) a main effect of study condition, a main effect of retention interval, and an interaction between study condition and retention interval

A) a main effect of study condition and an interaction between study condition and retention interval

7. Test-retest reliability is determined by: A) administering the same measure to the same sample at two different points in time and calculating the correlation between individuals' performance on the two administrations. B) administering the same measure to two different samples at two different points in time and calculating the correlation between individuals' performance at the two different times C) correlating the odd numbered items of a measure with an individual's performance on the even numbered items of that same measure. D) correlating the odd numbered items of a measure with an individual's performance on the even numbered items of a different measure.

A) administering the same measure to the same sample at two different points in time and calculating the correlation between individuals' performance on the two administrations

79. The expected frequencies across all cells of the chi-square should: A) always add up to the size of your sample. B) always add up to the size of your population. C) be 5 times the number of participants. D) be 3 times the number of participants.

A) always add up to the size of your sample.

6. The relation depicted in the scatterplot is potentially deceptive because of this problem. A) an outlier B) restriction of range C) poor reliability D) poor validity

A) an outlier

95. Researchers wondered whether support for privatizing public schools (support or not support) depended on a person's political affiliation (Democrat, Republican, or Independent). What statistical test would you use to analyze these data? A) chi-square test for independence B) chi-square test for goodness-of-fit C) 2 2 between-groups ANOVA D) Kruskal-Wallis H test

A) chi-square test for independence

80. The table constructed for a chi-square test of independence is a: A) contingency table. B) source table. C) frequency table. D) periodic table.

A) contingency table.

15. If between-groups variance is much larger than within-groups variance, then we infer that the sample means are: A) different from one another and reject the null hypothesis. B) similar to one another and fail to reject the null hypothesis. C) different from one another and fail to reject the null hypothesis. D) similar to one another and reject the null hypothesis.

A) different from one another and reject the null hypothesis.

35. MSBetween is obtained by: A) dividing SSBetween by dfBetween. B) dividing SSBetween by SSWithin. C) dividing dfBetween by SSBetween. D) dividing SSWithin by SSWithin.

A) dividing SSBetween by dfBetween

28. If we violate the assumption that our samples are randomly selected it affects our ability to: A) generalize the results of our study beyond our sample. B) differentiate between-groups variance and within-groups variance. C) meet the homogeneity of variance assumption. D) reject the null hypothesis.

A) generalize the results of our study beyond our sample

38. The grand mean is the: A) mean of all the scores in the study, regardless of the condition. B) average of each of your group means. C) mean of all the scores in the study squared. D) average difference of each of your group means.

A) mean of all the scores in the study, regardless of the condition.

60. The degrees of freedom for the interaction in a two-way ANOVA is calculated by: A) multiplying together the degrees of freedom associated with each of your main effects. B) adding together the degrees of freedom associated with each of your main effects. C) subtracting the degrees of freedom for your first main effect from that of your second main effect. D) subtracting a single participant from each cell of the study and then adding the results for all of the cells.

A) multiplying together the degrees of freedom associated with each of your main effects.

8. One problem with determining the reliability of a test using test-retest reliability is that: A) practice effects may occur. Having previously taken a test may change performance when that test is retaken. B) test-retest reliability does not provide any information about the validity of a test. C) most people perform worse when taking a test for the second time. D) participants may refuse to take the test for a second time.

A) practice effects may occur. Having previously taken a test may change performance when that test is retaken.

31. Between-groups degrees of freedom is calculated by: A) subtracting 1 from the total number of groups you have. B) multiplying the number of subjects you have by the number of conditions in your study and then subtracting 1. C) subtracting 1 from the total number of subjects that you have. D) subtracting 1 from the number of subjects within each group and then adding those together.

A) subtracting 1 from the total number of groups you have

20. With two groups, the square root of F is equal to: A) t. B) 0.0. C) 1.0. D) 2t.

A) t.

43. A post-hoc test is warranted when: A) the F is significant and we have more than two groups. B) we fail to reject the null hypothesis in an ANOVA. C) we reject the null hypothesis when performing an independent-groups t test. D) we have an a priori prediction about which group means will differ.

A) the F is significant and we have more than two groups.

71. The appropriate statistic for analyzing data in a situation in which both the independent and dependent variables are nominal is: A) the z test. B) analysis of variance. C) the chi-square. D) the independent-samples t test.

A) the z test.

68. If we have more than one dependent variable and we would like to analyze our data using analysis of variance, what form of ANOVA would we use? A) two-way analysis of variance B) analysis of covariance C) multivariate analysis of variance D) mixed-design analysis of variance

A) two-way analysis of variance

23. If your p level is .05 and the null hypothesis is true, what is the probability that you will make a Type I error (i.e., that you will fail to reject the null hypothesis)? A) 0.90 B) 0.05 C) 0.95 D) The probability is impossible to determine from the provided information.

B) 0.05

62. A researcher performs a 2 3 ANOVA with 5 participants in each cell of the study design. What is the degrees of freedom for the interaction? A) 6 B) 2 C) 3 D) 5

B) 2

48. The owners of the SciFi channel are interested in whether watching the SciFi channel causes people to become "geeky," and whether any such effects depend on a person's gender. They hire you to design and carry out the appropriate study. You design a study in which you randomly assign an equal number of men and women to watch either 0, 3, 5, or 9 hours of the SciFi channel each week for 6 weeks. How many cells does your study have? A) 2 B) 4 C) 6 D) 8

B) 4

26. In which of the following situations would it be necessary to use a between-groups ANOVA? A) A longitudinal study follows a group of kindergarten children through high school and assesses their Body Mass Index at four timepoints. B) A researcher classifies a group of college students on the basis of their political leanings, as either liberal, conservative, libertarian, or green. C) A researcher is interested in the effects of distraction on driving performance and randomly assigns participants to one of three distraction groups. D) A researcher is interested in whether a sensitivity training class changes attitudes toward minority populations. The researcher assesses these attitudes before and after the sensitivity training class.

B) A researcher classifies a group of college students on the basis of their political leanings, as either liberal, conservative, libertarian, or green

4. What effect does restricting the range of either of our variables have on the r statistic? A) A restricted range will have no effect on the value of r. B) A restricted range may either increase or decrease the value of r. C) A restricted range leads to an underestimation of the value of r. D) A restricted range leads to an overestimation of the value of r.

B) A restricted range may either increase or decrease the value of r.

22. Why can't a researcher just run multiple t tests when the independent variable has more than two levels? A) As you run more statistical tests, it becomes harder and harder to reject the null hypothesis. B) As you run more statistical tests, the probability that you will make a Type I error in one of the tests increases. C) As you run more statistical tests, you lose degrees of freedom. D) As you run more statistical tests, the probability that you will make a Type III error in one of those tests increases.

B) As you run more statistical tests, the probability that you will make a Type I error in one of the tests increases

34. The symbol for variance in the ANOVA is: A) s2, which stands for standard deviation squared. B) MS, which stands for means square. C) SD2, which stands for standard deviation squared. D) MS2, which stands for means square.

B) MS, which stands for means square.

56. The figure reflects a main effect of cognitive strategy. What best describes that main effect? A) People using both distraction and sensation-monitoring cognitive strategies were able to keep their hand in the ice water for longer than 60 seconds, on average. B) People using a sensation-monitoring strategy were able to keep their hand in the ice water for longer. C) People using a distraction strategy were able to keep their hand in the ice water for longer. D) The effect of cognitive strategy depended on the coping style of the participant. Those with an avoiding coping style kept their hand in the ice water longer when using a distraction strategy, but those with a monitoring coping style kept their hand in the ice water longer when using a sensation-monitoring strategy.

B) People using a sensation-monitoring strategy were able to keep their hand in the ice water for longer

55. The figure reflects a main effect of coping style. What best describes that main effect? A) People with monitoring and avoiding coping styles were able to keep their hand in the ice water for longer than 60 seconds, on average. B) People with an avoiding coping style were able to keep their hand in the ice water for longer. C) People with a monitoring coping style were able to keep their hand in the ice water for longer. D) The effect of coping style depended on the cognitive strategy employed. Those with an avoiding coping style kept their hand in the ice water longer when using a distraction strategy, but those with a monitoring coping style kept their hand in the ice water longer when using a sensation-monitoring strategy.

B) People with an avoiding coping style were able to keep their hand in the ice water for longer.

40. Lucille is interested in the effects of alcohol consumption on style of play while playing the videogame Sims. She asks a group of 15 college students to play Sims under one of the following conditions: no alcohol, 1 ounce, 2 ounces, or 3 ounces of alcohol. Lucille measures on a scale of 1 to 10 how prosocial their style of play is. After collecting the data, Lucille performs an ANOVA and finds that she can reject the null hypothesis. On the basis of this, what does Lucille know? A) She knows that greater levels of alcohol consumption are associated with a more prosocial style of play. B) She knows that there is a difference among the groups somewhere, but she does not know where. C) She knows that moderate alcohol consumption is associated with prosocial play, but that greater alcohol consumption is associated with an antisocial style of play. D) She knows that drinking any amount of alcohol affects the style of play.

B) She knows that there is a difference among the groups somewhere, but she does not know where.

52. The figure reflects an interaction. What best describes the interaction? A) On average, people in the study-test condition had better memory than people in the study-study condition. B) Those in the study-test condition performed more poorly on the 5-minute recall test than did those in the study-study condition, but at longer retention intervals (2-day and 1-week), those in the study-test condition performed better than those in the study-study condition. C) On average, memory performance decreased as the retention interval increased. D) On average, memory performance increased as the retention interval increased.

B) Those in the study-test condition performed more poorly on the 5-minute recall test than did those in the study-study condition, but at longer retention intervals (2-day and 1-week), those in the study-test condition performed better than those in the study-study condition.

92. Pugh (1983) was interested in whether there was a relationship between a defendant in a rape case being found guilty by a jury and the defense alleging that the victim was somehow at fault for the rape. She gathered data on rapes cases that were tried within a span of several years and classified each case as either guilty or not guilty and fault or no fault. What statistical test would you use to analyze these data? A) a chi-square test for independence B) a chi-square test for goodness-of-fit C) a 2 2 between-groups ANOVA D) a Kruskal-Wallis H test

B) a chi-square test for goodness-of-fit

27. The assumptions of the ANOVA are that samples: A) are selected randomly and that the samples come from populations with unequal variances. B) are selected randomly, the population distribution is normal, and the samples come from populations with equal variances. C) are selected randomly and the population distribution is normal. D) come from populations that are heteroscedastic and they are normally distributed.

B) are selected randomly, the population distribution is normal, and the samples come from populations with equal variances.

29. If you have unequal sample sizes, you can test for homoscedasticity A) by making sure that the within-groups variance is no more than two times the between-groups variance. B) by making sure that your largest sample variance is no more than two times the smallest variance. C) with an ANOVA. D) by making sure that your largest sample variance is no more than five times the smallest sample variance.

B) by making sure that your largest sample variance is no more than two times the smallest variance.

12. The average of all possible split-half correlations is: A) coefficient alpha, a measure of validity. B) coefficient alpha, a measure of reliability. C) the test-retest reliability. D) the test-retest validity.

B) coefficient alpha, a measure of reliability

9. The best and most widely used measure of reliability is: A) the split-half correlation, in which the odd and even numbered items of a measure are correlated to assess internal consistency. B) coefficient alpha, the average of all possible split-half correlations. C) the test-retest reliability. D) criterion-related reliability.

B) coefficient alpha, the average of all possible split-half correlations.

36. F is obtained by: A) dividing SSBetween by dfBetween. B) dividing MSBetween by MSWithin. C) dividing dfBetween by SSBetween. D) dividing SSBetween by SSWithin.

B) dividing MSBetween by MSWithin

10. A technique that quantifies the degree of association between two variables after statistically removing the association of a third variable with both of those two variables is: A) split-half reliability. B) partial correlation. C) concurrent validity. D) coefficient alpha.

B) partial correlation.

11. If one wishes to assess the relation between a farming county's average annual temperature and the crop yield, it may be important to take into account the overlapping variability that crop yield and temperature share with rainfall. To do so, one would compute a: A) split-half reliability. B) partial correlation. C) concurrent validity. D) coefficient alpha.

B) partial correlation.

44. Running post-hoc tests is different from running multiple t tests because: A) once you have calculated the ANOVA, you already have performed all the calculations necessary for the post-hoc tests. B) post-hoc tests control for the increase in Type I error associated with making multiple-group comparisons. C) post-hoc tests can only be conducted if we have a theory regarding where the differences are. D) There really is no difference between running post-hoc tests and running multiple t tests.

B) post-hoc tests control for the increase in Type I error associated with making multiple-group comparisons

65. An interaction is: A) residual within-groups variability. B) residual between-groups (i.e., between-cells) variability that is left over once the variability due to the main effects has been accounted for. C) between-groups variance divided by within-groups variance. D) within-groups variance divided by between-groups variance.

B) residual between-groups (i.e., between-cells) variability that is left over once the variability due to the main effects has been accounted for.

78. Degrees of freedom for the chi-square test of goodness-of-fit are determined by: A) subtracting 2 from the number of cells that there are (k - 2). B) subtracting 1 from the number of cells that there are (k - 1). C) multiplying the number of rows minus 1 times the number of columns minus 1. D) subtracting 1 from the number of participants that there are (N - 1).

B) subtracting 1 from the number of cells that there are (k - 1).

59. In a two-way ANOVA, the researcher makes decisions regarding: A) three separate null hypotheses. B) two separate null hypotheses. C) three interdependent null hypotheses. D) two interdependent null hypotheses.

B) two separate null hypotheses.

37. The F ratio is a ratio of: A) two (or more) sample means. B) two variances. C) sample means divided by sample variances. D) two sum of squares estimates.

B) two variances.

45. A hypothesis test with two nominal independent variables and an interval dependent variable is a: A) one-way ANOVA. B) two-way ANOVA. C) two-groups t test. D) two-groups z test.

B) two-way ANOVA

24. If your p level is .05 and the null hypothesis is true, what is the probability that you will not make a Type I error (i.e., you will fail to reject the null hypothesis)? A) 0.90 B) 0.05 C) 0.95 D) The probability is impossible to determine from the provided information.

C) 0.95

42. For an F distribution, with 2 degrees of freedom between and 27 degrees of freedom within, how many groups are being compared and how many participants are in each group assuming equal numbers of participants per group? A) 2 groups, with 27 participants in each group B) 2 groups, with 30 participants in each group C) 3 groups, with 10 participants in each group D) 4 groups, with 27 participants in each group

C) 3 groups, with 10 participants in each group

57. The figure reflects an interaction between coping style and cognitive strategy. What best describes that interaction? A) People using both distraction and sensation-monitoring cognitive strategies were able to keep their hand in the ice water for longer than 60 seconds, on average. B) People using a sensation-monitoring strategy were able to keep their hand in the ice water for longer. C) People using a distraction strategy were able to keep their hand in the ice water for longer. D) The effect of cognitive strategy depended on the coping style of the participant. Those with an avoiding coping style kept their hand in the ice water longer when using a distraction strategy, but those with a monitoring coping style kept their hand in the ice water longer when using a sensation-monitoring strategy.

C) People using a distraction strategy were able to keep their hand in the ice water for longer.

58. The figure reflects an interaction. Is this a quantitative or qualitative interaction? Why? A) This is a quantitative interaction because the effect of coping style does not reverse depending on the cognitive strategy employed. B) This is a qualitative interaction because the effect of coping style does not reverse depending on the cognitive strategy employed. C) This is a qualitative interaction because the effect of study condition reverses depending on the retention interval. Those with a monitoring coping style withstood pain longer when using the sensation-monitoring strategy, but those with an avoiding coping style withstood pain longer when using the distraction strategy. D) This is a quantitative interaction because the effect of cognitive strategy reverses depending on the coping style. Those with a monitoring coping style withstood pain longer when using the sensation-monitoring strategy, but those with an avoiding coping style withstood pain longer when using the distraction strategy.

C) This is a qualitative interaction because the effect of study condition reverses depending on the retention interval. Those with a monitoring coping style withstood pain longer when using the sensation-monitoring strategy, but those with an avoiding coping style withstood pain longer when using the distraction strategy.

94. If you have a single nominal variable and wish to compare the distribution of this nominal variable to an expected distribution, what kind of analysis would you use? A) a chi-square test for goodness-of-fit B) a chi-square test for independence C) a one-way ANOVA D) a single-sample t test

C) a one-way ANOVA

41. Clara works for an advertising firm and needs to understand how an individual's levels of experience with cooking (novice, intermediate, or expert) affect how he or she will rate a new group of cookware advertisements. What type of design would be best for Clara to use? A) a z test B) a t test C) a one-way between-groups ANOVA D) a one-way within-groups ANOVA

C) a one-way between-groups ANOVA

69. Imagine that educators in Cook County want to assess the efficacy of a new reading program they put in place. Therefore, they randomly assign some schools in the county to institute the new reading program and other schools to remain on the traditional reading program. When performing the analysis to determine whether students using the new reading program perform better, the educators control for socioeconomic status, a variable known to be related to educational outcomes. What kind of analysis have the educators performed? A) a two-way ANOVA B) a MANOVA C) an ANCOVA D) a one-way ANOVA

C) an ANCOVA

19. There is a different F distribution for every: A) sample size. B) level of your independent variable. C) combination of sample size and number of samples. D) within-groups degrees of freedom.

C) combination of sample size and number of samples.

1. The Pearson correlation coefficient is calculated as the average ________ of two standardized variables. A) z score B) reliability index C) cross-product D) validity coefficient

C) cross-product

46. In addition to assessing whether each of your independent variables has an effect on the dependent variable, a factorial ANOVA also allows you to: A) use multiple dependent measures in a single analysis. B) control for a third variable that might be related to your dependent measure prior to investigating the independent variable of interest. C) determine whether the effects of one factor depend on the other factor. D) partition out the variability due to individual differences and the variability due to measurement error.

C) determine whether the effects of one factor depend on the other factor.

13. The F is calculated by: A) dividing a measure of within-groups variability by a measure of between-groups variability. B) averaging the results from the t tests for all possible two-group comparisons. C) dividing a measure of between groups variability by a measure of within-groups variability. D) initially squaring all of your scores.

C) dividing a measure of between groups variability by a measure of within-groups variability.

76. In a study of simulated juror decision making, Braden-Maguire, Sigal, and Perrino (2005) investigated the type of verdict assigned by study participants after they read a 12-page summation of a case involving a battered woman who had shot and killed her husband. Of the 80 participants, 27 assigned a verdict of guilty, 49 a verdict of not guilty by reason of self-defense, and 4 a verdict of not guilty by reason of insanity. What type of chi-square test would the researchers use to determine if the distribution of verdicts differs from what would be expected by chance? A) association B) dissociation C) goodness-of-fit D) independence

C) goodness-of-fit

81. Degrees of freedom for the chi-square test of independence is determined by: A) subtracting 2 from the number of cells that there are (k - 2). B) subtracting 1 from the number of cells that there are (k - 1). C) multiplying the number of rows minus 1 times the number of columns minus 1. D) subtracting 1 from the number of participants that there are (N - 1).

C) multiplying the number of rows minus 1 times the number of columns minus 1.

5. Based on this scatterplot, what is the relation between an institution's student-faculty ratio and the number of applications it receives? A) perfect positive B) positive C) negative D) no relation

C) negative

64. In a two-way ANOVA, if you have a significant interaction: A) you know that at least one of your main effects is significant. B) the interpretation of significant main effects is independent of the interaction. C) the interpretation of any significant main effects will be qualified by the interaction. D) you know that both of your main effects are also significant.

C) the interpretation of any significant main effects will be qualified by the interaction.

72. Chi-square tests assess whether: A) two interval variables are associated. B) the means of two samples differ significantly from each other. C) the observed data differ from the pattern expected given the null hypothesis. D) the distributions of two variables are normally distributed.

C) the observed data differ from the pattern expected given the null hypothesis.

39. When F is significant: A) the values of the means that are closest together are the only ones that are significant. B) the values of the means that are farthest apart are the only ones that are significant. C) we do not know which specific means differ significantly. D) we fail to reject the null hypothesis.

C) we do not know which specific means differ significantly.

16. Interested in the effects of different kinds of instruction on videogame performance, Martin asks 30 college freshmen to each play an hour of Ratchet and Klank. Participants are randomly assigned to one of three instruction groups: (1) complete the tasks as quickly as possible, (2) conserve as much health as possible (i.e., play more carefully), or (3) find gold bolts (worth lots of money in equipment and ammunition). If Martin averages the scores for each instruction group and then compares them, any differences in the means of the instruction groups reflect: A) individual differences in hand-eye coordination. B) inherent differences in the ability of the college freshmen to play video games. C) within-groups variance. D) between-groups variance.

C) within-groups variance.

2. Which of the following values of the correlation coefficient indicates the weakest relationship between two variables? A) .42 B) -.30 C) -.87 D) .03

D) .03

14. If you have an interval dependent variable and your independent variable is nominal with three or more levels, you could use a(n) ________ to analyze your data. A) PRE test B) z test C) t test D) ANOVA

D) ANOVA

93. When your research design yields two variables that are both measured on an interval scale, then the appropriate statistical analysis to employ would be either a(n) ________ or a ________. A) ANOVA; t test B) independent-samples t test; dependent-samples t test C) correlation; regression D) Pearson correlation coefficient; Spearman correlation coefficient

D) Pearson correlation coefficient; Spearman correlation coefficient

74. Which of the following is not an assumption of the chi-square test? A) Participants are randomly selected from the population. B) The dependent variable is nominal. C) Each observation is independent of all other observations. D) The dependent variable is interval.

D) The dependent variable is interval.

53. The figure reflects an interaction. Is this a quantitative or qualitative interaction? Why? A) This is a quantitative interaction because the effect of study condition does not reverse depending on the retention interval. B) This is a qualitative interaction because the effect of study condition does not reverse depending on the retention interval. C) This is a quantitative interaction because the effect of study condition reverses depending on the retention interval. With the 5-minute retention interval, study-study is better than study-test, but with longer retention intervals, study-test is better than study-study. D) This is a qualitative interaction because the effect of study condition reverses depending on the retention interval. With the 5-minute retention interval, study-study is better than study-test, but with longer retention intervals, study-test is better than study-study.

D) This is a qualitative interaction because the effect of study condition reverses depending on the retention interval. With the 5-minute retention interval, study-study is better than study-test, but with longer retention intervals, study-test is better than study-study.

17. Tilbe wants to compare young children's verbal test scores across three experimental conditions (different levels of instruction from low to high) and one control group (no instruction). What type of test should she use? A) a z test B) a t test C) a Bonferroni test D) an ANOVA

D) an ANOVA

70. When you have one nominal variable, the appropriate statistical test to use is a chi-square test for: A) goodness-of-fit. B) independence. C) empowerment. D) association.

D) association.

30. If you have equal sample sizes, you can test for homoscedasticity: A) by making sure that the within-groups variance is no more than two times the between-groups variance. B) by making sure that the between-groups variance is no more than five times the within-groups variance. C) with an ANOVA. D) by making sure that your largest sample variance is no more than five times the smallest sample variance.

D) by making sure that your largest sample variance is no more than five times the smallest sample variance.

73. Unlike ANOVA, the values in the cells of a chi-square are: A) proportions. B) medians. C) means. D) counts or frequencies.

D) counts or frequencies.

18. Martin is interested in the effects of different kinds of instruction on videogame performance. Martin obtains 30 college freshmen and has each of them play 1 hour of Ratchet and Klank. Participants are randomly assigned to one of three instruction groups: (1) complete the tasks as quickly as possible, (2) conserve as much health as possible (i.e., play more carefully), or (3) find gold bolts (worth lots of money in equipment and ammunition). Obviously, even in a single instruction group, not all players will obtain the same final score. These differences in an instruction group reflect: A) between-groups variance. B) within-groups variance. C) effects of instruction. D) effects of confounding variables.

D) effects of confounding variables.

32. Within-groups degrees of freedom is calculated by: A) subtracting 1 from the total number of groups you have. B) multiplying the number of subjects you have by the number of conditions in your study and then subtracting 1. C) subtracting 1 from the total number of subjects that you have. D) for each condition, subtracting 1 from the number of subjects in that group, and then adding the totals for all of your groups together.

D) for each condition, subtracting 1 from the number of subjects in that group, and then adding the totals for all of your groups together.

77. In a study of simulated juror decision making, Braden-Maguire, Sigal, and Perrino (2005) investigated the type of verdict assigned by study participants after they read a 12-page summary of a case involving a battered woman who had shot and killed her husband. In particular, the researchers manipulated the race of the defendant (African American or Caucasian) and the type of abuse suffered (emotional or physical). The dependent variable was the number of guilty verdicts. What type of chi-square test would the researchers use to analyze these data? A) association B) dissociation C) goodness-of-fit D) independence

D) independence

75. A college instructor is interested in whether assigning mandatory homework affects students' grades. Since she is currently teaching two sections of the same class, the instructor assigns homework to one of the classes and just recommends homework problems to the second class. Then she determines the number of people in each class that will receive either an A, B, C, D, or F on the final exam. What type of statistical test would the instructor use to analyze her data? A) chi-square test for goodness-of-fit B) chi-square test for independence C) analysis of variance D) independent-samples t test

D) independent-samples t test

66. If an analysis of variance includes both within-groups factors and between-groups factors, we call it a: A) two-way ANOVA. B) complex-design ANOVA. C) between-within ANOVA. D) mixed-design ANOVA.

D) mixed-design ANOVA.

21. If there are only two samples and sample size is infinity, then the F distribution is the: A) sum of those two samples. B) t distribution. C) null hypothesis distribution for when N = 2. D) square of the z distribution

D) square of the z distribution

61. Within-groups degrees of freedom in a two-way ANOVA is calculated by: A) multiplying together the degrees of freedom associated with each of your main effects. B) adding together the degrees of freedom associated with each of your main effects. C) subtracting the degrees of freedom for your first main effect from that of your second main effect. D) subtracting a single participant from each cell of the study and then adding the results for all of the cells.

D) subtracting a single participant from each cell of the study and then adding the results for all of the cells.

33. The F statistic increases when: A) within-groups variance decreases. B) between-groups variance decreases. C) between-groups variance increases. D) within-groups variance decreases and between-groups variance increases.

D) within-groups variance decreases and between-groups variance increases