Exam 3 ch 12, 14-16

Exam 3 Instructions: The exam is open book and open notes. It is not open internet or friend/acquaintance/enemy, though, so make sure you don’t talk to anyone about the content of the exam until you are both finished. You can use any of the resources/keys/lectures Dr. Woestehoff posted on Moodle, though. The t and F distribution tables are on Moodle and in the back of your textbook in the appendices. You can submit your exam on Moodle by uploading a Word document or a PDF. Make sure to label each question. For example, you could write “1. Z” for question 1, if you chose response letter “z”. Multiple choice. 1. The percentage of variance accounted for by the treatment effect is usually known as _____ in published reports of ANOVA results. a. µ 2 b. η 2 c. σ 2 d. α 2 e. 2. What is the purpose for post hoc tests? a. to determine whether or not a Type I error was committed b. to determine how much difference exists between the treatments c. to determine which treatments are significantly different d. to determine whether or not the sample is normally distributed 3. In an analysis of variance, what is a factor ? a. a dependent variable b. an independent variable c. a treatment mean d. a treatment total e. 4. A one-way analysis of variance is used to evaluate the mean differences for a research study comparing FOUR treatments with a separate sample of n = 8 in each treatment. If the data produce an F-ratio of F = 5.50, then which statistical decision is correct? (hint: you’ll need to calculate df and identify the F-criticals). a. Reject the null hypothesis with α = .05 but not with α = .01. b. Reject the null hypothesis with either α = .05 or α = .01. c. Fail to reject the null hypothesis with either α = .05 or α = .01. d. There is not enough information to make a statistical decision.

5. Dr. Fuzzy wants to know whether cat people or dog people have better eyesight. She gets two groups of people together. One group likes dogs and the other group likes cats. Then, she gives everyone an eye test. What statistical test would be most appropriate to use? a. Independent-samples t test b. Related-samples t test c. Analysis of Variance (ANOVA) d. z-score for sample mean 6. Sir Mix-A-Lot wants to know whether listening to Mozart makes people happier. He gathers one group of people and gives them a questionnaire about their happiness level. Then he asks everyone to listen to some Mozart. Afterwards, everyone answers the happiness questionnaire again. Which statistical test is best to use? a. Independent-samples t test b. Related-samples t test c. Analysis of Variance (ANOVA) d. z-score for sample mean 7. What would the scatterplot show for data that produce a correlation of +0.88? a. points clustered close to a line that slopes up to the right b. points clustered close to a line that slopes down to the right c. points widely scattered around a line that slopes up to the right d. points widely scattered around a line that slopes down to the right 8. Which correlation value shows the greatest strength or consistency of relationship? a. –0.90 b. +0.74 c. +0.85 d. –0.33 9. The results from a research study indicate that adolescents who watch more violent content on television also tend to engage in more violent behavior than their peers. The correlation between amount of TV violent content and amount of violent behavior is an example of a ____. a. positive correlation b. negative correlation c. correlation near zero d. correlation near one 10. A researcher obtains a Pearson correlation of r = 0.43. t = 2.02 and df = 18. For a two- tailed test, which of the following accurately describes the significance of the correlation? a. The correlation is significant with α = .05 but not with α = .01. b. The correlation is significant with either α = .05 or α = .01. c. The correlation is not significant with either α = .05 or α = .01. d. The correlation is equal to zero. e.