# If the F-statistic is significant for a Within

QUESTION 1If the F-statistic is significant for a Within Subjects ANOVA, we should do what type of follow tests?Chi-Square TestsDependent t-testsIndependent t-testsCorrelations1 points QUESTION 2A study by Bettmann (2007) published in the Journal of the American Psychoanalytic Association assessed whether the attachment relationships between adolescents and their parents change as a result of a residential wilderness treatment experience for the adolescents. Participants completed the Adolescent Attachment Questionnaire at the start and at the end of the wilderness program. Which statistical test should be used to determine whether the wilderness treatment affected attachment relationships?A.z testB.effect size testC.single-sample t testD.dependent-samples t test1 points QUESTION 3A paired-samples t test is reported as t(15) = 0.918, p > 0.05, d = 0.17. What is the effect size for this statistical test?A.This is a large effect.B.There is no effect size reported.C.This is a medium effect.D.This is a small effect.1 points QUESTION 4What would be the decision for the following paired-samples t test: t(24) = 4.11, p < 0.05?A.fail to reject the null hypothesisB.reject the research hypothesisC.reject the null hypothesisD.fail to reject the research hypothesis1 points QUESTION 5Assume the following for a paired-samples t test: N = 9, Mdifference = 13.19, s = 22.3. What is the t statistic?A.7.43B.0.59C.4.40D.1.771 points QUESTION 6Twenty college students experience the effects of alcohol on reaction time. They perform very basic timed responses in a driving simulator both before and after consuming several alcoholic beverages. The researcher collects a reaction time result for each of the 20 students before and after intoxication, for a total of 40 measures. What are the degrees of freedom for this study?A.20B.40C.19D.391 points QUESTION 7A psychologist is interested in whether working memory is influenced by sleep loss. The psychologist administers a measure of working memory to a group of subjects at 8 A.M. on Day One of the study and then again at 8 A.M. on Day Two of the study, after keeping the subjects awake the entire night. Does sleep loss affect working memory? What statistical analysis we should be performed to answer this question?A.z testB.standard deviation analysisC.dependent-samples t testD.single-sample t test1 points QUESTION 8A researcher studies 45 volunteer citizens from a small community and asks them about the amount of caffeine (in milligrams) they ingest before and after lunch each day. The null hypothesis for this paired-samples study could be:A.there is no difference between the amount of caffeine ingested before and after lunch.B.there is a difference between the amount of caffeine ingested before and after lunch.C.more caffeine is ingested before lunch.D.more caffeine is ingested after lunch.1 points QUESTION 9A researcher studies 45 volunteer citizens from a small community and asks them about the amount of caffeine (in milligrams) they ingest before and after lunch each day. Two measures are taken from each participant for a total of 90 data points. The degrees of freedom for this paired-samples study are:A.89.B.44.C.45.D.90.1 points QUESTION 10You are conducting an independent t-test to compare men and women on a performance test. If the standard deviation for men 7 for a sample of 35 and the standard deviation for women is 6 for a sample of 82, what is the pooled standard deviation? Round to the second decimal place as needed.1 points QUESTION 11The F ratio measures two sources of variability: within-groups variance and between-groups variance. True False1 points QUESTION 12What is the degrees of freedom error for a Within Subjects ANOVA, if the number of time points is 3 and the number of subjects is 26?1 points QUESTION 13Find the Mean Squared Between. The sample sizes for each of the groups is 24 and the sample means are as follows 25, 24, 14. Round tothe second decimal place if needed.1 points QUESTION 14A positive correlation between head size and foot size indicates that:A.people with larger feet also tend to have larger heads.B.having large feet causes a person to have a large head.C.people with larger feet tend to have smaller heads.D.having a large head causes a person to have large feet.1 points QUESTION 15What is the research hypothesis when testing for significance using the Pearson correlation coefficient?A.? 1 = ?2B.? = 1C.r = 0D.?01 points QUESTION 16What kind of correlation would one expect to find between the age of a car (nonclassic) and its value?A.negativeB.positiveC.perfect positiveD.zero1 points QUESTION 17What is the direction of this scatterplot?positivenegative1 points QUESTION 18When conducting a hypothesis test for the Pearson correlation coefficient, degrees of freedom is calculated by:A.?(X – MX)2.B.(N1 – 1)(N2 – 1).C.N – 1.D.N – 2.1 points QUESTION 19According to guidelines published by Cohen (1988), a correlation value of _____ is considered small, _____ is medium, and _____ is strong.A.0.40; 0.60; 0.80B.0.25; 0.50; 0.75C.0.10; 0.30; 0.50D.1.00; 2.00; 3.001 points QUESTION 20Order the scatterplots by strength from lowest to strongest.a)b)c) – 1. 2. 3. a – 1. 2. 3. b – 1. 2. 3. c1 points QUESTION 21The denominator of the Pearson correlation equation corrects for _____ and _____ issues present in the numerator.A.sample size; nonnormalityB.negative values; variabilityC.sample size; variabilityD.negative values; nonlinear data1 points QUESTION 22Researchers who study the process of reading in children have discovered that better readers make smoother eye movements across the page (i.e., there is a positive correlation between reading skill and the smoothness of the eye movements). Which statement is a possible cause of the correlation between smooth eye movements and reading ability?A.The ability to make smooth eye movements improves reading ability.B.Having good reading skills allows a child to make smooth eye movements.C.Some third factor might cause both smooth eye movements and improved reading ability.D.All of these options are possible causes of the correlation.1 points QUESTION 23Which of these correlation coefficients allows a perfect prediction of scores on one variable from knowledge of scores on the other variable?A.–1.00B.0.50C.0D.2.001 points QUESTION 24The Pearson correlation coefficient is a statistic that measures:A.relatedness in terms of variability between variables.B.an association between scale, ordinal, and nominal variables.C.a linear relation between two scale variables.D.the causal association between scale variables.1 points QUESTION 25You are conducting a dependent t-test: There is a repeated measure design and there is a pre and post test. What is the average of the difference scores?Your difference scores should be calculated like this: Difference = pre – post. Round to the second decimal place, if needed.prepost339267586511 points QUESTION 26If the is 12, the is 1, and the is 6, what should the F-statistic be for a Within Subjects ANOVA? Round to the second decimal place, if needed. Hint: You only need 2 of the numbers for the calculation.1 points QUESTION 27If the sample size is 40 and the calculated t-statistic is 1.5, what is the p-value for a not equal to research hypothesis?.141667.1547892.138920.1123491 points QUESTION 28If the is 96 and the is 29, what is the F-statistic? Round to the second decimal place, if needed.1 points QUESTION 29If the F-statistic is significant and you are comparing 3 sample means, what can you conclude?At least one of the sample means is different.The mean for sample1 is different than the mean for sample 3.The mean for sample 1 is different than the mean for sample 2.The mean for sample 2 is different than the mean for sample 3.1 points QUESTION 30A dependent t-test is used when your sample is paired. True False1 points QUESTION 31A professor is not sure which exam (1 or 2) that students do better on. The professor samples 10 students and records the exam 1 and exam 2 scores for each of the 10 students. Thus, there are 20 observations. What should the research hypothesis be? Assume that difference scores are calculated as such: difference = exam 2 – exam 1.1 points QUESTION 32For an independent t-test: It is hypothesized that men score higher than women. What could be the research hypothesis?1 points QUESTION 33An independent t-test is used when your sample is paired. True False1 points QUESTION 34For an independent t-test: It is hypothesized that women score higher than men. What could be the research hypothesis?1 points QUESTION 35The statement “On average, older adults have a different response time than younger adults” is an example of:A.the null hypothesis.B.statistical significance.C.the research hypothesis.D.effect size.1 points QUESTION 36Dr. Jameson wanted to know if IQ scores differed between male and female participants in his study. He gave 28 participants an IQ test and then compared IQ scores for gender differences. He hypothesized that there would be a statistically significant gender difference in IQ scores. Contrary to Dr. Jameson’s hypothesis, there were no differences in IQ scores between men and women in his study. From the results of the study, Dr. Jameson must _____ the null hypothesis and _____ the research hypothesis.A.retest; rejectB.fail to reject; rejectC.reject; retestD.reject; fail to reject1 points QUESTION 37Mehl (2007) published in the journal Science the results of an extensive study of 396 men and women comparing the number of words uttered per day by each sex. Which statistical test should Mehl use to analyze the data?A.z testB.independent-samples t testC.dependent-samples t testD.single-sample t test1 points QUESTION 38In a(n) _____, a within-groups design with two groups is used to compare the distribution of mean difference scores.A.single-sample t testB.paired-samples t testC.independent-samples t testD.z test1 points QUESTION 39Dr. Jameson wanted to know if IQ scores differed between male and female participants in his study. He gave 28 participants an IQ test and then compared IQ scores for gender differences. He hypothesized that there would be a statistically significant gender difference in IQ scores. Contrary to Dr. Jameson’s hypothesis, there were no differences in IQ scores between men and women in his study. Which test was Dr. Jameson MOST likely to use to test his hypothesis?A.independent-samples t testB.z testC.single-samples t testD.paired-samples t test1 points QUESTION 40When statisticians describe pooling the variances, they mean:A.taking the average of the two variances, accounting for sample size.B.adding the variances of the two samples.C.taking the average of the two variances, disregarding sample size.D.adding the standard deviations of the two samples.1 points QUESTION 41Suppose there is a repeated measure design. There are 4 time points and 3 subjects. The mean for subject 1 is 6, the mean for subject 2 is 5, and the mean for subject 3 is 1. What is the ? Hint: Find the grand mean first from the subject’s means. Make sure you take in account the number of time points. Round to the second decimal place if need.1 points QUESTION 42If the F-statistic is not significant for a Within Subjects ANOVA, we should conduct follow up t-tests. True False1 points QUESTION 43If the sample sizes for each group is 23, and the sum of squares for each group is as follows: 6, 6, and 3, what is the Mean Squared Within? Round to the second decimal place, if needed.1 points QUESTION 44What number must the F-statistic be higher than to be significant?Note: Being greater than this number, does not guarantee it will be significant (depends on the degrees of freedom), but it must at least greater than this number to be significant.1 points QUESTION 45A one-way within-groups ANOVA on 2 and 15 degrees of freedom results in an F statistic of 3.12. What decision should be made about the hypothesis based on this statistic?A.Fail to reject the null hypothesis and conclude there is no effect of the independent variable.B.Reject the null hypothesis and conclude there are differences among the levels of the independent variable.C.Reject the null hypothesis and conclude the independent variable has no effect.D.Fail to reject the null hypothesis because the F statistic does not exceed the critical cutoff.1 points QUESTION 46Buying jeans can be a challenge for women. A local shop owner wants to be selective in what brands of jeans she carries in her store. She gets six of her closest friends to try five different pairs of jeans, with the requirement that they wear each pair for two whole days, without washing, and they rate the jeans at the end of the second day. What research design should she use to analyze her data?A.one-way within-groups ANOVAB.independent-samples t testsC.paired-samples t testsD.one-way between-groups ANOVA1 points QUESTION 47A researcher wants to examine people’s preference for pets by having 10 people act as “foster owners” for four different types of family pets: dogs, cats, birds, and fish. The participants will foster each type of pet for one week, and a scale measure will be used to assess preference. Which research design should be used?A.one-way between-groups ANOVAB.one-way within-groups ANOVAC.paired-samples t testsD.correlation1 points QUESTION 48What is the correct formula for degrees of freedom associated with the subjects sum of squares?A.Ngroups – 1B.n – 1C.n – 2D.Ntotal – 11 points QUESTION 49Dr. Sanders was interested in investigating the effects of stress on memory. He exposed participants to public speaking stress and room temperature stress and gave them a memory measure immediately after exposure to the two stressors. Dr. Sanders also gave participants the memory measure at baseline, when they first entered the research laboratory. Dr. Sanders hypothesized that participants’ memories would be most affected by the two stressors compared to the baseline condition. What statistical test should Dr. Sanders use to test her hypothesis?A.between-groups ANOVAB.dependent samples t testC.independent samples t testD.within-groups ANOVAQUESTION 1If the F-statistic is significant for a Within Subjects ANOVA, we should do what type of follow tests?Chi-Square TestsDependent t-testsIndependent t-testsCorrelations1 points QUESTION 2A study by Bettmann (2007) published in the Journal of the American Psychoanalytic Association assessed whether the attachment relationships between adolescents and their parents change as a result of a residential wilderness treatment experience for the adolescents. Participants completed the Adolescent Attachment Questionnaire at the start and at the end of the wilderness program. Which statistical test should be used to determine whether the wilderness treatment affected attachment relationships?A.z testB.effect size testC.single-sample t testD.dependent-samples t test1 points QUESTION 3A paired-samples t test is reported as t(15) = 0.918, p > 0.05, d = 0.17. What is the effect size for this statistical test?A.This is a large effect.B.There is no effect size reported.C.This is a medium effect.D.This is a small effect.1 points QUESTION 4What would be the decision for the following paired-samples t test: t(24) = 4.11, p < 0.05?A.fail to reject the null hypothesisB.reject the research hypothesisC.reject the null hypothesisD.fail to reject the research hypothesis1 points QUESTION 5Assume the following for a paired-samples t test: N = 9, Mdifference = 13.19, s = 22.3. What is the t statistic?A.7.43B.0.59C.4.40D.1.771 points QUESTION 6Twenty college students experience the effects of alcohol on reaction time. They perform very basic timed responses in a driving simulator both before and after consuming several alcoholic beverages. The researcher collects a reaction time result for each of the 20 students before and after intoxication, for a total of 40 measures. What are the degrees of freedom for this study?A.20B.40C.19D.391 points QUESTION 7A psychologist is interested in whether working memory is influenced by sleep loss. The psychologist administers a measure of working memory to a group of subjects at 8 A.M. on Day One of the study and then again at 8 A.M. on Day Two of the study, after keeping the subjects awake the entire night. Does sleep loss affect working memory? What statistical analysis we should be performed to answer this question?A.z testB.standard deviation analysisC.dependent-samples t testD.single-sample t test1 points QUESTION 8A researcher studies 45 volunteer citizens from a small community and asks them about the amount of caffeine (in milligrams) they ingest before and after lunch each day. The null hypothesis for this paired-samples study could be:A.there is no difference between the amount of caffeine ingested before and after lunch.B.there is a difference between the amount of caffeine ingested before and after lunch.C.more caffeine is ingested before lunch.D.more caffeine is ingested after lunch.1 points QUESTION 9A researcher studies 45 volunteer citizens from a small community and asks them about the amount of caffeine (in milligrams) they ingest before and after lunch each day. Two measures are taken from each participant for a total of 90 data points. The degrees of freedom for this paired-samples study are:A.89.B.44.C.45.D.90.1 points QUESTION 10You are conducting an independent t-test to compare men and women on a performance test. If the standard deviation for men 7 for a sample of 35 and the standard deviation for women is 6 for a sample of 82, what is the pooled standard deviation? Round to the second decimal place as needed.1 points QUESTION 11The F ratio measures two sources of variability: within-groups variance and between-groups variance. True False1 points QUESTION 12What is the degrees of freedom error for a Within Subjects ANOVA, if the number of time points is 3 and the number of subjects is 26?1 points QUESTION 13Find the Mean Squared Between. The sample sizes for each of the groups is 24 and the sample means are as follows 25, 24, 14. Round tothe second decimal place if needed.1 points QUESTION 14A positive correlation between head size and foot size indicates that:A.people with larger feet also tend to have larger heads.B.having large feet causes a person to have a large head.C.people with larger feet tend to have smaller heads.D.having a large head causes a person to have large feet.1 points QUESTION 15What is the research hypothesis when testing for significance using the Pearson correlation coefficient?A.? 1 = ?2B.? = 1C.r = 0D.?01 points QUESTION 16What kind of correlation would one expect to find between the age of a car (nonclassic) and its value?A.negativeB.positiveC.perfect positiveD.zero1 points QUESTION 17What is the direction of this scatterplot?positivenegative1 points QUESTION 18When conducting a hypothesis test for the Pearson correlation coefficient, degrees of freedom is calculated by:A.?(X – MX)2.B.(N1 – 1)(N2 – 1).C.N – 1.D.N – 2.1 points QUESTION 19According to guidelines published by Cohen (1988), a correlation value of _____ is considered small, _____ is medium, and _____ is strong.A.0.40; 0.60; 0.80B.0.25; 0.50; 0.75C.0.10; 0.30; 0.50D.1.00; 2.00; 3.001 points QUESTION 20Order the scatterplots by strength from lowest to strongest.a)b)c) – 1. 2. 3. a – 1. 2. 3. b – 1. 2. 3. c1 points QUESTION 21The denominator of the Pearson correlation equation corrects for _____ and _____ issues present in the numerator.A.sample size; nonnormalityB.negative values; variabilityC.sample size; variabilityD.negative values; nonlinear data1 points QUESTION 22Researchers who study the process of reading in children have discovered that better readers make smoother eye movements across the page (i.e., there is a positive correlation between reading skill and the smoothness of the eye movements). Which statement is a possible cause of the correlation between smooth eye movements and reading ability?A.The ability to make smooth eye movements improves reading ability.B.Having good reading skills allows a child to make smooth eye movements.C.Some third factor might cause both smooth eye movements and improved reading ability.D.All of these options are possible causes of the correlation.1 points QUESTION 23Which of these correlation coefficients allows a perfect prediction of scores on one variable from knowledge of scores on the other variable?A.–1.00B.0.50C.0D.2.001 points QUESTION 24The Pearson correlation coefficient is a statistic that measures:A.relatedness in terms of variability between variables.B.an association between scale, ordinal, and nominal variables.C.a linear relation between two scale variables.D.the causal association between scale variables.1 points QUESTION 25You are conducting a dependent t-test: There is a repeated measure design and there is a pre and post test. What is the average of the difference scores?Your difference scores should be calculated like this: Difference = pre – post. Round to the second decimal place, if needed.prepost339267586511 points QUESTION 26If the is 12, the is 1, and the is 6, what should the F-statistic be for a Within Subjects ANOVA? Round to the second decimal place, if needed. Hint: You only need 2 of the numbers for the calculation.1 points QUESTION 27If the sample size is 40 and the calculated t-statistic is 1.5, what is the p-value for a not equal to research hypothesis?.141667.1547892.138920.1123491 points QUESTION 28If the is 96 and the is 29, what is the F-statistic? Round to the second decimal place, if needed.1 points QUESTION 29If the F-statistic is significant and you are comparing 3 sample means, what can you conclude?At least one of the sample means is different.The mean for sample1 is different than the mean for sample 3.The mean for sample 1 is different than the mean for sample 2.The mean for sample 2 is different than the mean for sample 3.1 points QUESTION 30A dependent t-test is used when your sample is paired. True False1 points QUESTION 31A professor is not sure which exam (1 or 2) that students do better on. The professor samples 10 students and records the exam 1 and exam 2 scores for each of the 10 students. Thus, there are 20 observations. What should the research hypothesis be? Assume that difference scores are calculated as such: difference = exam 2 – exam 1.1 points QUESTION 32For an independent t-test: It is hypothesized that men score higher than women. What could be the research hypothesis?1 points QUESTION 33An independent t-test is used when your sample is paired. True False1 points QUESTION 34For an independent t-test: It is hypothesized that women score higher than men. What could be the research hypothesis?1 points QUESTION 35The statement “On average, older adults have a different response time than younger adults” is an example of:A.the null hypothesis.B.statistical significance.C.the research hypothesis.D.effect size.1 points QUESTION 36Dr. Jameson wanted to know if IQ scores differed between male and female participants in his study. He gave 28 participants an IQ test and then compared IQ scores for gender differences. He hypothesized that there would be a statistically significant gender difference in IQ scores. Contrary to Dr. Jameson’s hypothesis, there were no differences in IQ scores between men and women in his study. From the results of the study, Dr. Jameson must _____ the null hypothesis and _____ the research hypothesis.A.retest; rejectB.fail to reject; rejectC.reject; retestD.reject; fail to reject1 points QUESTION 37Mehl (2007) published in the journal Science the results of an extensive study of 396 men and women comparing the number of words uttered per day by each sex. Which statistical test should Mehl use to analyze the data?A.z testB.independent-samples t testC.dependent-samples t testD.single-sample t test1 points QUESTION 38In a(n) _____, a within-groups design with two groups is used to compare the distribution of mean difference scores.A.single-sample t testB.paired-samples t testC.independent-samples t testD.z test1 points QUESTION 39Dr. Jameson wanted to know if IQ scores differed between male and female participants in his study. He gave 28 participants an IQ test and then compared IQ scores for gender differences. He hypothesized that there would be a statistically significant gender difference in IQ scores. Contrary to Dr. Jameson’s hypothesis, there were no differences in IQ scores between men and women in his study. Which test was Dr. Jameson MOST likely to use to test his hypothesis?A.independent-samples t testB.z testC.single-samples t testD.paired-samples t test1 points QUESTION 40When statisticians describe pooling the variances, they mean:A.taking the average of the two variances, accounting for sample size.B.adding the variances of the two samples.C.taking the average of the two variances, disregarding sample size.D.adding the standard deviations of the two samples.1 points QUESTION 41Suppose there is a repeated measure design. There are 4 time points and 3 subjects. The mean for subject 1 is 6, the mean for subject 2 is 5, and the mean for subject 3 is 1. What is the ? Hint: Find the grand mean first from the subject’s means. Make sure you take in account the number of time points. Round to the second decimal place if need.1 points QUESTION 42If the F-statistic is not significant for a Within Subjects ANOVA, we should conduct follow up t-tests. True False1 points QUESTION 43If the sample sizes for each group is 23, and the sum of squares for each group is as follows: 6, 6, and 3, what is the Mean Squared Within? Round to the second decimal place, if needed.1 points QUESTION 44What number must the F-statistic be higher than to be significant?Note: Being greater than this number, does not guarantee it will be significant (depends on the degrees of freedom), but it must at least greater than this number to be significant.1 points QUESTION 45A one-way within-groups ANOVA on 2 and 15 degrees of freedom results in an F statistic of 3.12. What decision should be made about the hypothesis based on this statistic?A.Fail to reject the null hypothesis and conclude there is no effect of the independent variable.B.Reject the null hypothesis and conclude there are differences among the levels of the independent variable.C.Reject the null hypothesis and conclude the independent variable has no effect.D.Fail to reject the null hypothesis because the F statistic does not exceed the critical cutoff.1 points QUESTION 46Buying jeans can be a challenge for women. A local shop owner wants to be selective in what brands of jeans she carries in her store. She gets six of her closest friends to try five different pairs of jeans, with the requirement that they wear each pair for two whole days, without washing, and they rate the jeans at the end of the second day. What research design should she use to analyze her data?A.one-way within-groups ANOVAB.independent-samples t testsC.paired-samples t testsD.one-way between-groups ANOVA1 points QUESTION 47A researcher wants to examine people’s preference for pets by having 10 people act as “foster owners” for four different types of family pets: dogs, cats, birds, and fish. The participants will foster each type of pet for one week, and a scale measure will be used to assess preference. Which research design should be used?A.one-way between-groups ANOVAB.one-way within-groups ANOVAC.paired-samples t testsD.correlation1 points QUESTION 48What is the correct formula for degrees of freedom associated with the subjects sum of squares?A.Ngroups – 1B.n – 1C.n – 2D.Ntotal – 11 points QUESTION 49Dr. Sanders was interested in investigating the effects of stress on memory. He exposed participants to public speaking stress and room temperature stress and gave them a memory measure immediately after exposure to the two stressors. Dr. Sanders also gave participants the memory measure at baseline, when they first entered the research laboratory. Dr. Sanders hypothesized that participants’ memories would be most affected by the two stressors compared to the baseline condition. What statistical test should Dr. Sanders use to test her hypothesis?A.between-groups ANOVAB.dependent samples t testC.independent samples t testD.within-groups ANOVAQUESTION 50If the SS within is is 72 and the SS subjects is 15, what is the SS Error ?