PROBLEMS

1. The results from a two-factor experiment can be presented in a matrix with the levels of one factor forming the rows and the levels of the second factor forming the columns, with a separate sample in each of the matrix cells. Using this matrix structure, describe what is meant by the main effects for each factor and the interaction between factors. (6 points)
2. The following table summarizes the results of a two-factor ANOVA evaluating an independent-measures experiment with two levels of factor A, three levels of factor B, and n = 5 subjects in each separate sample. Fill in all missing values in the table. (Hint: Start with the df column.) (7.5 points)
   
3. The following data were obtained from a two-factor independent-measures experiment. (15 points)

1. Perform all of the necessary calculations and put the calculated values in an ANOVA summary table.
2. Calculate effect sizes, post hoc tests, and write a conclusion based on your results.

4. A professor obtains SAT scores and freshman grade point averages (GPAs) for a group of n = 15 college students. The SAT scores have a mean of M = 580 with SS = 22,400, and the GPAs have a mean of 3.10 with SS = 1.26, and SP = 84.

1. Find the regression equation for predicting GPA from SAT scores.
2. What percentage of the variance in GPAs is accounted for by the regression equation? (Compute the correlation, r, and then find r ² )
3. Does the regression equation account for a significant portion of the variance in GPA? Use a = .05 to evaluate the F-ratio.

6. We are examining the results of a study of eye-witness testimony. The investigators wish to know whether recall of important information is influenced by the severity of the crime and the amount of time that passes before the witness is asked to recall important events. The study is described below. The first independent variable is severity of the crime. A videotape is made of a man stealing a woman's purse in an uncrowded clothing store. A second videotape is made, using the same actors, of a man using a gun to rob the cash register of the same clothing store. In this scenario, the woman is a sales clerk behind the cash register and there are two people standing at the counter. The second independent variable is time to recall. Subjects are asked to view the videotape and to imagine that they are at the crime scene. In the "immediate" condition, subjects are asked a series of questions about the crime within 10 minutes of viewing the videotape. In the

"delay" condition, they are asked the same series of questions about the crime 20-30 minutes after viewing the tape. This is designed to be similar to an actual crime scene where there is some delay when taking witness statements.

Perform the appropriate analysis using SPSS. Please write up the results as you would in a scientific paper. For any significant main effects, please report the effect size. Please turn in the relevant portions of your SPSS output. (12 points)

7. Students often complain that having final exams at scheduled times that are different from regular class sessions disrupts their circadian rhythms and affects their performance. You suspect that this might be so and that the impact would be greatest for more difficult exams. To test this, you conduct a 2 x 3 between-subjects experiment in which difficulty level and time of testing are varied for a sample of students who are taking final exams at "different" times. Using the data presented below, test whether performance depends on time of day and difficulty level of the exam. Perform the appropriate analysis using SPSS. Please write up the results as you would in a scientific paper. For any significant main effects, please report the effect size. Please turn in the relevant portions of your SPSS output. (12 points)

8. An experiment was conducted to study the effect of punishment on the behavior of sociopaths. Twelve sociopaths and twelve normal controls were randomly assigned to a shock-punishment, social-punishment, or money-loss-punishment condition. During the experiment, shock, social, or money-loss punishment was delivered for errors on an experimental task. The data in the table show the number of errors made by each individual in each condition. What effect did the different types of punishment have on the performance of the sociopaths? Perform the appropriate analysis using SPSS. Please write up the results as you would in a scientific paper. For any significant main effects, please report the effect size. Please turn in the relevant portions of your SPSS output. (12 points)

9. Ten students who initially scored low on the verbal portion of the SAT and 10 who initially scored high are randomly assigned to instruction and no instruction groups. Their gain scores (how much they improved in their SAT verbal score) appear below. Perform the appropriate analysis using SPSS. Please write up the results as you would in a scientific paper. For any significant main effects, please report the effect size. Please turn in the relevant portions of your SPSS output. (12 points)

Price: $41.3

Solution: The downloadable solution consists of 21 pages, 2030 words and 24 charts.
Deliverable: Word Document