# Describing Correlation Coefficients

PART A: Describing Correlation Coefficients

Describe in words the nature of the relationship between each pair of variables as indicated by the value of the correlation coefficient. Be sure to include:

a. the direction of the relationship.

b. the strength of the relationship.

c. a verbal description of the way the variables “go together.

1. r = ­.96 between craving for pizza and ability to concentrate on studying.

2. r = +.02 between length of marriage and marital satisfaction.

3. r = +.55 between parent and child intelligence test scores.

4. r = ­.90 between amount of alcohol consumed and performance on a motor coordination task.

5. r = +.75 between amount of money won and the number of hot dogs purchased at race tracks.

6. r = +.67 between scores on a hyperactivity scale and an aggressiveness scale.

7. r = ­.82 between a job applicant’s age and likelihood of being hired.

8. r = +.06 between the number of yearly predictions by psychics and the number of correct predictions.

PART B: Applying Design Concepts

Review and respond to each of the following items. Be sure to answer all questions presented in each item.

1. Your dog gets lonely while you are at work and consequently engages in destructive activities such as pulling down curtains or strewing wastebasket contents all over the floor. You decide that playing a radio while you are gone might help. How might you determine whether this “treatment” is effective?

2. Your best friend frequently suffers from severe headaches. You’ve noticed that your friend consumes a great deal of diet cola, and so you consider the hypothesis that the artificial sweetener in the cola is responsible for the headaches. Devise a way to test your hypothesis using a single case design. What do you expect to find if your hypothesis is correct? If you obtain the expected results, what do you conclude about the effect of the artificial sweetener on headaches?

3. Dr. Smith learned that one sorority on campus had purchased several Macintosh computers and another sorority had purchased several Windows­based computers. Dr. Smith was interested in whether the type of computer affects the quality of students’ papers, so he went to each of the sorority houses to collect samples of papers from the members. Two graduate students in the English department then rated the quality of the papers. Dr. Smith found that the quality of the papers was higher in one sorority than in the other. What are the independent and dependent variables in this study? Identify the type of design that Dr. Smith used. What variables are confounded with the independent variable? Design a true experiment that would address Dr. Smith’s original question.

4. Gilovich (1991) described an incident that he read about during a visit to Israel. A very large number of deaths had occurred during a brief time period in one region of the country. A group of rabbis attributed the deaths to a recent change in religious practice that allowed women to attend funerals. Women were immediately forbidden from attending funerals in that region, and the number of deaths subsequently decreased. How would you explain this phenomenon?

11/23/2016 Upload Assignment: Week 6 Lab Activity – PSYC­330­OL50­…

5.. The captain of each precinct of a metropolitan police department selected two officers to participate in a program designed to reduce prejudice by increasing sensitivity to racial and ethnic group differences and community issues. The training program took place every Friday morning for 3 months. At the first and last meetings, the officers completed a measure of prejudice. To assess the effectiveness of the program, the average prejudice score at the first meeting was compared with the average score at the last meeting; it was found that the average score was in fact lower following the training program. What type of design is this? What specific problems arise if you try to conclude that the training program was responsible for the reduction in prejudice?

6. A student club is trying to decide whether to implement a peer tutoring program for students who are enrolled in the statistics class in your department. Club members who have completed the statistics class would offer to provide tutoring to students currently enrolled in the class. You decide to take the lessons of program evaluation seriously, and so you develop a strategy to conduct evaluation research.

a. How would you measure whether there is a need for such a program?

b. Briefly describe how you might implement a tutoring program. How would you monitor the program?

c. Propose a quasi­experimental design to evaluate whether the program is effective.

d. How might you determine the economic efficiency of such a program?

7. Many elementary schools have implemented a daily “sustained silent reading” period during which students, faculty, and staff spend 15­20 minutes silently reading a book of their choice. Advocates of this policy claim that the activity encourages pleasure reading outside the required silent reading time; design a nonequivalent control group pretest­posttest quasi­experiment to test this claim. Include a well­reasoned dependent measure as well.

8. Dr. Cardenas studied political attitudes among different groups of 20­, 40­, and 60­year­olds. Political attitudes were found to be most conservative in the age­60 group and least conservative in the age­20 group.

a. What type of method was used in this study?

b. Can you conclude that people become more politically conservative as they get older? Why or why not?

c. Propose alternative ways of studying this topic.

PART C: Title Page Practice using APA Format

Please use correct APA format to type a title page for an essay or research report. You MUST USE the following information to type the title page, and be sure to attach the title page as a separate document to this assignment!

Manuscript page header: Cognitive and linguistic