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Q: A researcher is interested in the social behavior of mice. He hypothesizes that mice from Strain A will be more social than mice from Strain B, and Strain B will be significantly more social than mice from Strain C. Mice from each of the three different strains (20 mice in each strain) are raised in a laboratory. The mice are group housed with members of its own strain. All the mice receive the exact same amount of food, water, and light over the first 10 weeks of life. At 11 weeks of age, each mouse is placed in a cage with a novel mouse from his own strain. The mouse's investigatory behavior toward the other mouse is timed for 10 minutes.Given the above result, what might the experimenter do next?a) abandon the hypothesisb) run the experiment again with some mice group-housed and others singly-housedc) run the same statistical tests again to see if the results changed) both b and c

Q: A researcher is interested in the social behavior of mice. He hypothesizes that mice from Strain A will be more social than mice from Strain B, and Strain B will be significantly more social than mice from Strain C. Mice from each of the three different strains (20 mice in each strain) are raised in a laboratory. The mice are group housed with members of its own strain. All the mice receive the exact same amount of food, water, and light over the first 10 weeks of life. At 11 weeks of age, each mouse is placed in a cage with a novel mouse from his own strain. The mouse's investigatory behavior toward the other mouse is timed for 10 minutes.The researcher then decided to run the experiment again. This time mice of each strain were singly housed, isolated from members of their own strain for the 11 weeks. Now she finds that p = .048. This suggestsa) isolation reduces social interaction.b) the researcher's original hypothesis was correct.c) isolation might bring about strain differences in investigatory behavior.d) mice enjoy isolation.

Q: A researcher is interested in the social behavior of mice. He hypothesizes that mice from Strain A will be more social than mice from Strain B, and Strain B will be significantly more social than mice from Strain C. Mice from each of the three different strains (20 mice in each strain) are raised in a laboratory. The mice are group housed with members of its own strain. All the mice receive the exact same amount of food, water, and light over the first 10 weeks of life. At 11 weeks of age, each mouse is placed in a cage with a novel mouse from his own strain. The mouse's investigatory behavior toward the other mouse is timed for 10 minutes.If, after running the appropriate analysis, the researcher finds a result with p = .50, what can she conclude?a) Her hypothesis was supported by the analysis.b) Different strains of mice do exhibit significantly different levels of social behavior.c) Strain A is more social than Strain B, but not more than Strain C.d) Different strains of mice do not exhibit significantly different levels of social behavior.

Q: A researcher is interested in the social behavior of mice. He hypothesizes that mice from Strain A will be more social than mice from Strain B, and Strain B will be significantly more social than mice from Strain C. Mice from each of the three different strains (20 mice in each strain) are raised in a laboratory. The mice are group housed with members of its own strain. All the mice receive the exact same amount of food, water, and light over the first 10 weeks of life. At 11 weeks of age, each mouse is placed in a cage with a novel mouse from his own strain. The mouse's investigatory behavior toward the other mouse is timed for 10 minutes.Which statistical analysis is most appropriate for testing this researcher's hypothesis?a) One-way ANOVAb) Repeated-measures ANOVAc) Factorial ANOVAd) Independent samples t-test

Q: The Morris water maze is used to examine spatial learning in animals. Mice, who are good swimmers, are placed in a large pool of water and must learn to find a clear platform located just under the water surface. The platform is their only escape from the pool. If they do not find the platform, they have to continue swimming until we take them out.If we think that we may have some aberrant times, what is the best way to identify them?a) create a boxplotb) prepare a stem-and-leaf displayc) use a pie chartd) calculate the variance

Q: The Morris water maze is used to examine spatial learning in animals. Mice, who are good swimmers, are placed in a large pool of water and must learn to find a clear platform located just under the water surface. The platform is their only escape from the pool. If they do not find the platform, they have to continue swimming until we take them out.When mice perform in a Morris Water maze they sometimes become confused on a particular trial and take a long time to get to the platform. On other trials they are just lucky and go straight to it. How can we eliminate or reduce the influence of these unusual times?a) compare medians instead of meansb) use trimmed meansc) toss out scores that we don"t liked) both a and b

Q: The Morris water maze is used to examine spatial learning in animals. Mice, who are good swimmers, are placed in a large pool of water and must learn to find a clear platform located just under the water surface. The platform is their only escape from the pool. If they do not find the platform, they have to continue swimming until we take them out.We want to report an effect size estimate that reflects the fact that the animals were able to find the platform faster on the 10th trial that they did on the first trial. What would be the best measure to report?a) the difference in mean times on the two trials in questionb) the standardized difference in mean timesc) the correlation between performance on the first and tenth trialsd) the squared correlation between the two trials

Q: The Morris water maze is used to examine spatial learning in animals. Mice, who are good swimmers, are placed in a large pool of water and must learn to find a clear platform located just under the water surface. The platform is their only escape from the pool. If they do not find the platform, they have to continue swimming until we take them out.8 We want to compare the amount of time the mice spent swimming in the first trial to the amount of time they spent swimming in the tenth trial. What statistical test should be conducted on these data?a) t-testb) correlationc) factorial ANOVAd) one way ANOVA

Q: The Morris water maze is used to examine spatial learning in animals. Mice, who are good swimmers, are placed in a large pool of water and must learn to find a clear platform located just under the water surface. The platform is their only escape from the pool. If they do not find the platform, they have to continue swimming until we take them out.For one of the trials, the platform was removed from the pool and the amount of time the mouse spent in each of the four quadrants of the tank was recorded. What statistical test should be conducted on these data?a) t-testb) correlationc) factorial ANOVAd) repeated-measures ANOVA

Q: In an experiment aimed at evaluating the effect of a memory-enhancing drug on the recall of a previously learned response. Either the drug or a placebo was administered to different groups of rats before the memory test. There were three trials of the memory test, and the dependent variable was the time it took the animal to make the correct response.Why do we not need to use a multiple comparison procedure to compare the drug and control conditions?a) The difference is obvious.b) The difference is unimportant.c) There are only two groups.d) The test would not be appropriate unless we had at least four groups.

Q: In an experiment aimed at evaluating the effect of a memory-enhancing drug on the recall of a previously learned response. Either the drug or a placebo was administered to different groups of rats before the memory test. There were three trials of the memory test, and the dependent variable was the time it took the animal to make the correct response.It seems reasonable that there is some sort of relationship between the number of trials it took to learn a response and the speed of response on the test trials. It would be interesting to know how the drug affects this relationship. How might you go about looking at this question?a) Run a t test between the two groups' performance on the first test trial.b) Correlate the number of learning trials with the speed of performance on the test trials.c) Correlate number of learning trials and speed on test trials separately for the two drug conditions.d) Use the Mann-Whitney test to compare the groups.

Q: In an experiment aimed at evaluating the effect of a memory-enhancing drug on the recall of a previously learned response. Either the drug or a placebo was administered to different groups of rats before the memory test. There were three trials of the memory test, and the dependent variable was the time it took the animal to make the correct response.We want to compute an effect size estimate for the difference between drug and placebo treatments. We will take as our dependent variable for this computation each animal's mean response time over the three trials. What would be the best estimate of effect size?a) The difference between the means of the two groups.b) The difference between the group means divided by the square root of the pooled variance estimate.c) The difference between the means divided by the standard deviation of the control group.d) None of the above would be of any value.

Q: What assumption(s) would we need to make for this analysis?a) The observations are independent.b) The observations are normally distributed.c) The animals are randomly assigned to drug treatmentsd) both b and c

Q: Suppose the analysis reveals a significant drug by trial interaction. What would we conclude about the effect of the drug on memory?a) The effect of the delay is different for the drug and the placebo.b) The drug has no effect on memory.c) The trials have no affect on memory.d) No conclusion can be reached without looking at the percent correct responses.

Q: In an experiment aimed at evaluating the effect of a memory-enhancing drug on the recall of a previously learned response. Either the drug or a placebo was administered to different groups of rats before the memory test. There were three trials of the memory test, and the dependent variable was the time it took the animal to make the correct response.The proper analysis to evaluate the drug enhancement of memory is a(n)a) t-test.b) ANOVA with a within-subjects effect of trials.c) one-way ANOVA.d) factorial ANOVA.

Q: 45 A critic for the Food Network asked five world-renown chefs to taste three types of olive oil and rate them on a scale from 0 to 100 where 100 represents the highest quality. Analyze and interpret the following data using the Friedman test.Chef Oil 1 Oil 2 Oil 31 50 100 02 75 95 253 45 70 304 55 85 405 65 90 15

Q: 44 A Pediatrician wants to know if number of children in the family is related to how early parents arrive for regularly scheduled pediatric visits. The data follow in terms of the number of minutes early. Analyze and interpret the data using the Kruskal-Wallis procedure.1 Child 2 Children 3 or More Children10 1 08 0 015 2 2.55 3 1.759 1.5 2.7512 20 6.514 7 1311 6 0.521 4

Q: 43 Re-analyze the previous data using the normal approximationa) Calculate and interpret z.b) Which analysis is more appropriate? Explain.

Q: 42 A teacher wanted to see if her students could complete a multiplication review sheet more quickly after practicing for a week. The total number of seconds it took each time are reported below. Calculate Wilcoxon's matched pairs signed ranks test on the following data and describe the results.Student 1 2 3 4 5 6 7 8 9 10 11Before 60 75 48 90 30 55 75 80 90 85 60After 50 60 49 75 35 45 68 59 92 70 50

Q: 41 Re-analyze the previous data using the normal approximation. a) Calculate z and describe your conclusions. b) Which analysis is more appropriate for these data? Explain.

Q: 40 The following depression data using the two-tailed Mann-Whitney test. Describe your conclusions.Experimental ControlGroup Group 150 90140 4080 10070 60220 200360 150190

Q: 39 Under what conditions would you calculate in the Mann-Whitney test?

Q: 38 In a Kruskal-Wallis one-way analysis of variance, would you retain or reject the null hypothesis given the following information: a) H = 15.6, df = 8 b) H = 35.75, df = 25 c) H = 45.7, df = 30

Q: 37 Would you reject or retain the null hypothesis in a Wilcoxon's matched-pairs signed rank test given the following information and assuming a one-tailed test and = .05:a) n = 5, T = 0b) n = 12, T = 19c) n = 28, T = 129

Q: 36 Would you reject or retain the null hypothesis in a Mann-Whitney test given the following information and assuming a one-tailed test and = .05:a) n1 = 1, n2 = 25, W = 3b) n1 = 5, n2 = 6, W = 14c) n1 = 8, n2 = 9, W = 60

Q: 35 The ranks of these numbers: 1, 5, 2, 4, 5 are 1, 4.5, 2, 3, 4.5.

Q: 34 Friedman's rank test for k-related samples is to Wilcoxon's matched-pairs signed ranks test as a repeated-measures ANOVA is to a paired samples t-test.

Q: 33 As the sample size increases, non-parametric statistics approach normal.

Q: 32 When using Wilcoxon's matched pairs-signed ranks test, the rank of the difference between related scores is calculated.

Q: 31 Friedman's rank test for k-correlated samples is used to assess the degree of association between ranks, much like a correlation coefficient.

Q: 30 The Mann-Whitney test is used to compare the rank scores of two groups.

Q: 29 In distribution-free tests, you usually reject the null hypothesis when the obtained value is smaller than the critical value.

Q: 28 Distribution free tests are more sensitive to means than to medians.

Q: 27 Distribution-free tests tend to be greatly affected by outliers.

Q: 26 Non-parametric tests are those that do not rely on parameter estimation or strong assumptions about distributions.

Q: 25 The Mann-Whitney test is to independent samples t test as Wilcoxon's matched-pairs signed-ranks test is to a) Kruskal-Wallis ANOVA. b) one-way repeated-measures ANOVA. c) related sample means t-test. d) Friedman's rank test for k correlated samples.

Q: 24+ One major argument promoting the use of parametric tests over distribution-free tests is that parametric tests are a) easier to calculate. b) usually robust enough to be unaffected by violation of assumptions. c) less affected by outliers than distribution-free tests. d) used less frequently and therefore must be more elite.

Q: 23 The Friedman test a) ranks the scores within each subject. b) is appropriate when we have several repeated measures on each subject. c) is largely insensitive to outliers. d) all of the above

Q: 22 The Kruskal-Wallis test is based ona) thet distribution.b) the z distribution.c) the distribution.d) the F distribution.

Q: 21 The Kruskal-Wallis test is appropriate when a) we have several independent groups. b) we want to compare group medians rather than means. c) we are worried about outliers. d) all of the above

Q: 20 When using Wilcoxon's test for paired samples, subjects whose two scores are equal, yielding a difference score of zero, are usually a) given a random sign. b) omitted from the data. c) punished. d) given a plus sign for one score and a minus sign for another.

Q: 19 Wilcoxon's test for paired samples focuses on a) the mean of the two samples. b) the sign of the difference scores. c) the relative magnitude of the difference scores. d) both b and c

Q: 18 Distribution-free tests and parametric tests differ in their null hypotheses in that a) distribution-free tests have a less specific null hypothesis. b) distribution-free tests make very strong assumptions about the mean. c) distribution-free tests don"t really have a null hypothesis. d) parametric tests have rather loose null hypotheses.

Q: 17+ Tied scores often present a problem in distribution-free tests. The most common way to deal with them in a Mann-Whitney test is to a) flip a coin. b) use a random number table. c) assign tied ranks. d) throw out the tied data.

Q: 16+ In the previous example of the smoking cessation study we might be tempted to apply Friedman's test, because it can handle similar data. This would be a bad idea because a) Friedman's test really won"t handle these data. b) Friedman's test will not use some of the information inherent in the data. c) Milton Friedman is a conservative economist, and we only like liberal psychologists. d) We really should use Friedman's test.

Q: 15+ In the previous question, the most appropriate test would be a) the Mann-Whitney test. b) the Wilcoxon signed-ranks test. c) Friedman's test. d) the Kruskal-Wallis test.

Q: 14+ Assume that we asked 20 subjects to participate in a smoking cessation study. We recorded their craving for a cigarette before and after applying a nicotine patch. One reason we might want to use a distribution-free test is because a) we have too few subjects for a parametric test. b) there are some outliers that we don"t want to have undue influence on the results. c) the data are normally distributed. d) the subjects are all male.

Q: 13 When we have relatively large sample sizes, the distribution-free tests for comparing two groups or sets of data discussed in the text have a) a chi-square approximation. b) a normal approximation. c) no solution. d) problems.

Q: 12+ With at least some distribution-free tests, a two-tailed test a) is not appropriate. b) requires an additional calculation. c) is more likely to be significant than a one-tailed test. d) is automatic.

Q: 11+ One of the unusual things about distribution-free tests is that they are often set up so that a) they only work with equal sample sizes. b) the null hypothesis is never assumed to be true. c) we reject the null hypothesis when our test statistic is too small, rather than too large. d) they are all named after people.

Q: 10+ Each of the distribution-free tests that are covered in the book deal with a) ranks. b) means. c) standard deviations. d) raw data.

Q: 9 If the null hypothesis is true and we run the Mann-Whitney test on our data, the expectation is that a) the difference scores will all be zero. b) the test will be significant. c) the sum of the ranks in the two groups will be approximately equal (assuming equal sample sizes). d) the number of subjects in each group will be about the same.

Q: 8+ Which of the distribution-free tests is roughly equivalent to the t test for two independent means? a) the Mann-Whitney test b) Wilcoxon's signed-ranks matched-pairs test c) Friedman's test d) the Kruskal-Wallis test

Q: 7+ Distribution-free tests are a) more sensitive to the effects of outliers than parametric tests. b) more sensitive to the effects of scores near the mean than parametric tests. c) largely unaffected by the presence of outliers. d) both a and c

Q: 6 When the assumptions behind parametric tests are not met, a) they are not useful tests. b) they cannot even be computed. c) distribution-free tests may have more power. d) none of the above

Q: 5+ The major advantage of distribution-free tests is that a) they do not rely on assumptions as severe as those for parametric tests. b) they have more power. c) they are substantially easier to run. d) they are more common.

Q: 4 When we speak about rank-randomization tests we are talking about procedures that a) deal with ranks. b) ask how ranks would be distributed if the data were random. c) form the basis of many distribution-free tests. d) all of the above

Q: 3 Which of the following is a nonparametric procedure? a) at test. b) the analysis of variance. c) the Mann-Whitney test. d) Pearson's correlation coefficient (r).

Q: 2+ If the usual assumptions behind parametric tests are met (at least approximately), a) distribution-free tests are more powerful than parametric tests. b) distribution-free tests are somewhat less powerful than parametric tests. c) the tests are indistinguishable. d) you shouldn"t use a parametric test.

Q: 1 A distribution-free test a) is almost synonymous with a nonparametric test. b) is a test that makes few assumptions about the distribution from which the data were drawn. c) usually has less power than a parametric test. d) all of the above

Q: 56 Based on the previous example: a) What are the df? b) Calculate and interpret Chi-square.

Q: 55 A political science student did a survey to see if the political affiliation of voters was related to whether or not they would consider voting for a progressive candidate in the upcoming gubernatorial race. How would you calculate the marginals and expected frequencies for each cell.

Q: 54 Calculate and interpret the z score based on the proportion of youth who end up in prison using the data from the previous example.

Q: 53 Calculate and interpret Chi-square based on the contingency table you created.

Q: 52 A social worker has been asked to testify before her state legislature about the impact of long-term foster care on child outcomes and government spending. She knows that 60% of children who remained in the foster care system without being adopted ended up in prison. The figure for foster care children who were eventually adopted was 25%. These data were based on 500 children who remained in foster care and 800 children who were eventually adopted. Create the appropriate contingency table.

Q: 51 Calculate and interpret Chi-square for the previous example.

Q: 50 A researcher wants to be sure that her random assignment to groups has been working. She wants to be sure that socio-economic status and treatment group are independent. Ideally, given her particular sample, there would be an equal number of people in each category. Calculate the marginal totals and the expected frequencies for each cell. Experimental Group Control GroupBelow poverty line 22 28Above Poverty line 28 22

Q: 49 Assuming the student body in the previous example is 30% male and 70% female, a) What are the expected values b) Calculate and interpret Chi-square

Q: 48 A professor believes that a greater proportion of females than males have enrolled in her class. Assuming an equal number of males and females in the student body, calculate Chi-square, and evaluate her hypothesis based on the following data.Males Enrolled Females Enrolled10 20

Q: 47 Indicate whether or not the following Chi-square statistics are significant: a) 2.75; k =2 b) 11.00; k =5 c) 12.40; df = 6

Q: 46 In a contingency table, the expected frequency of any given cell is represented by this formula:

Q: 45 A marginal total is the sum of the level of one variable across all of the levels of the other variable.

Q: 44 In a Chi-square including two variables, one with 4 categories, and the other with 3 categories, the df = 6.

Q: 43 In order for a Chi-square test to be valid, a general rule of thumb is that every cell have expected frequencies greater than or equal to 10.

Q: 42 It is appropriate to use Chi-square when data from the same subject are in multiple cells.

Q: 41 If a Chi-square is conducted based on data from 30 people who are categorized into one of 4 possible categories, the df = 26.

Q: 40 In a Chi-square, k refers to the number of categories.

Q: 39 Expected frequencies are the expected value for the number of observations in a cell if the alternative hypothesis is true.

Q: 38 A Goodness-of-fit test compares the observed number of frequencies with predicted frequencies.

Q: 37 Chi-square is used to analyze continuous data.